Browsing by Author "Mackraj, Irene."

Now showing 1 - 12 of 12

The effect of isolated and nanoencapsulated flavonoids from Eriocephalus africanus on apoptotic factors and microRNA expression in cancer.
(2020) Magura, Judie.; Mackraj, Irene.; Moodley, Roshila.
Cancer continues to be a major health burden worldwide, with millions of new cases being diagnosed each year. Among women breast cancer remains a leading cause of cancer-related morbidity and mortality globally, despite the significant advances in detection and individualised treatments. The ideal non-surgical approach for the treatment of breast cancer would be anticancer therapeutics that are delivered directly to the tumour site for complete elimination of cancerous cells without being toxic to surrounding healthy cells. However, current chemotherapeutics encounter numerous challenges due to adverse side effects and progressive drug resistance albeit effective. In light of this, identifying new effective therapies with minimal toxic and chemosensitizing effects as well as target specificity is crucial in combating cancer. Emerging evidence has supported the use of plant-derived chemicals as novel alternative treatment options, owing to their minimal side effects and toxicity. Plant-derived polyphenols have gained considerable research interest due to their ability to inhibit proliferation, initiate apoptosis and arrest the cell cycle of cancerous cells by modulating related pathways. Furthermore, incorporation of active plant-derived polyphenols into novel technologies such as nanosystems, offers more optimal therapies through improved bioavailability and target specificity. In this regard, this study demonstrates, for the first time, the potential of phytochemicals isolated from the methanolic extract of the medicinal plant, Eriocephalus africanus, as an alternative therapeutic strategy in breast cancer treatment using ER-positive human adenocarcinoma (MCF-7) cell lines. Spectroscopic techniques including nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (IR) and mass spectrometry (MS) were used to identify the isolated compounds as hesperidin (flavanone), luteolin (flavone) and apigenin (flavone). Preliminary anticancer screening using the 3-(4,5dimethylthiazolyl)-2,5-diphenyl-tetrazolium bromide (MTT) assay revealed hesperidin and luteolin to be potent against MCF-7. Dysregulated cellular apoptotic death is a hallmark of cancer and chemotherapy resistance; thus, the development of anticancer drugs targeting apoptosis is a widely used, effective anticancer treatment strategy. In this study, the efficacy of hesperidin and luteolin in targeting the apoptotic pathway was evaluated. Treatment of breast cancer cells with hesperidin and luteolin resulted in the downregulated expression of key anti-apoptotic Bcl-2; upregulated expression of pro-apoptotic Bax and caspases -8, -9 and -3. In addition, hesperidin and luteolin demonstrated the ability to effect epigenetic control through altering the expression of apoptotic microRNAs (-16, -21 and -34a). Moreover, treatment with hesperidin and luteolin resulted in significant accumulation of MCF-7 apoptotic cells into the G0/G1 and sub-G1 cell cycle phases, respectively. Encapsulation of hesperidin into nanoemulsions improved the cytotoxic and apoptotic effects in MCF-7 without being cytotoxic to non-cancerous human cell lines (HEK 293), halted the progression of the MCF-7 cells in the G2/M phase, and exhibited potential therapeutic activity through inhibiting the expression of oncomirs miR-21 and -155 overexpressed in breast cancer. Encapsulation of luteolin into solid nanoparticles generated from cleaved stearylamine exhibited non-selective cytotoxicity and decreased cell viability (< 10%) in both MCF-7 and HEK 293 cells, thus no further investigations were conducted using luteolin-loaded solid nanoparticles. Collectively, findings from this study provide new evidence on the effects of flavonoids isolated from E. africanus on apoptotic and epigenetic control in breast cancer, increasing our knowledge of the molecular basis of their anticancer activity.
The effect of sildenafil citrate and kraussianone-2 on pre-eclampsia-like manifestations in Sprague-Dawley rats.
(2011) Ramesar, Shamal Vinesh.; Mackraj, Irene.; Moodley, Jagidesa.; Gathiram, Premjith.
Pre-eclampsia, often described as toxaemia of pregnancy, historically represents one of the most widely investigated conditions relating to human reproduction. To date no firm cure has been found and a clear, well defined mechanism has not been ascribed to the pathogenesis of the disease. Researchers seem to focus on single pathways in isolation of others. The disease rather represents a multitude of possible underlying pathologies nvolving genetics, immune dysregulation, vascular maladaptation, and sociobiological factors thus complicating the approach to treatment. However, a central theme is the presence of reduced placental perfusion resulting in a hypoxic and/or ischaemic placenta and the subsequent secretion of various factors that initiate the maternal syndrome. It is within this context that we examine how an intervention such as increasing placental perfusion may represent a promising treatment strategy for this disease. We sought to manipulate the vasodilatory mechanisms of the uterine vasculature using sildenafil citrate and a flavonoid extracted from Eriosema kraussianum (Kr2), in Sprague-Dawley rats that exhibited preeclampsia-like manifestations. Both treatment regimens improved fetal outcomes and reduced blood pressure amplification and proteinuria. They also reduced the plasma concentrations of the two anti-angiogenic factors; sFlt1 and sEng. Only sildenafil citrate improved nitric oxide levels which was expected, suggesting that Kr2 causes vasodilation by some other mechanism. Nevertheless, both compounds improved both pup and placental weights, suggesting that they also improve utero-placental perfusion. These findings that selective uterine vascular dilation improves placental perfusion may be promising in averting possible death to mothers and their babies from pre-eclampsia especially in low resource environments.
Effect of titanium dioxide nanoparticle aggregation on mouse myoblast cellular cytotoxicity and nitric oxide synthesis.
(2017) Phoswa, Wendy.; Mackraj, Irene.
ABSTRACT Introduction: The emerging interest of engineered titanium dioxide nanoparticles (TiO2 NPs) in medical, agricultural, industrial and manufacturing sectors have raised health questions worldwide. Therefore, the objective was to assess the effect of physiochemical properties of titanium dioxide nanoparticles (TiO2 NPs) on the cellular cytotoxicity, proliferation and physiological properties. Methods: TiO2 NPs were suspended in varying concentrations of bovine serum albumin (BSA γ-globulin) and characterised using nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) for the determination of particle size, aggregation state, and zeta potential. The effect of TiO2 physiochemical properties on cellular cytotoxicity and proliferation was assessed in vitro on mouse myoblast (C2C12) cells using the MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] and BrdU assay respectively. Nitric oxide (NO), a major signalling molecule was measured using a biochemical test. in vitro. Results: There was an increase in size, distribution, surface charge and reduced aggregation in BSA stabilised TiO2 NPs in comparison to non-stabilised TiO2 NPs. Increased cytotoxicity of cells treated with monodispersed TiO2 NPs compared to cells treated with aggregated TiO2 NPs (p<0.001) was observed. A significant decrease in cell viability in cells treated with BSA (0.5, 0.8 and 1.0 mg/ml) stabilised TiO2 NPs (40, 120, 240, 320 and 400 mg/ml) in a dose-dependent manner in contrast to cells treated with BSA (0.3 and 1.5 mg/ml) stabilised TiO2 NPs (40, 120, 240, 320 and 400 mg/ml) dose dependent manner was observed (p<0.05). However, there was a greater decrease in cell viability in BSA (0.8 mg/ml) stabilised TiO2 NPs (40, 120, 240, 320 and 400 mg/ml) compared to other BSA concentration (p<0.05). In addition, there was a significant difference in DNA proliferation of the control and treated cells. A significant difference in DNA damage was observed in cells treated with BSA compared to non-treated cells, especially at BSA concentrations of 0.8 and 1.5 mg/ml. A significant difference in DNA damage in cells treated with TiO2 NPs in combination with BSA (0.8 and 1.5 mg/ml) was obtained. There was greater difference in DNA damage of cells exposed to TiO2 NPs in combination with 0.8 mg/ml compared to TiO2 NPs in combination with 1.5 mg/ml. More interestingly there was a significant difference between the levels of nitric oxide (NO) in 40 and 400 mg/ml TiO2 NPs treated cells in comparison to cells treated with BSA (0.3-1.5 mg/ml) stabilised TiO2 NPs (40 and 400 mg/ml) (p<0.05). There was a significance difference in the levels of NO between cells treated with 40 mg/ml TiO2 NPs vs (0.3, 0.5, 0.8 and 1.0 mg/ml) BSA stabilised TiO2 NPs (40 mg/ml) (p<0.05). However, there was greater significant difference between 400 mg/ml TiO2 treated cells vs BSA (0.5, 0.8 and 1.0 mg/ml) stabilised 400 mg/ml TiO2 NPs (400 mg/ml) (p<0.05). Discussion/Conclusion: The use of BSA as a nanoparticle stabiliser impacted upon physiochemical properties for the determination of in vitro cytotoxicity. These findings indicate that particle size needs to be taken into consideration when assessing nanoparticle toxicity. The results also indicate that less aggregated TiO2 NPs are more toxic than more aggregated TiO2 NPs and have a potential to inhibit cellular signalling mechanisms such as NO signalling and cellular proliferation.
The effect of vitamin B-6 deficiency on the levels of tissue copper, iron and zinc in the rat.
(1989) Mackraj, Irene.; Burger, F. J.
No abstract available.
An evaluation of the chemical composition and the in vitro and in vivo antihypertensive activity of extracts of Tulbaghia acutiloba Harv. in an L-NAME induced hypertensive model.
(2019) Arhin, Isaiah.; Mackraj, Irene.
The increasing prevalence of hypertension over the years has been identified as a major contributor to high morbidity and mortality, globally and locally, in Africa, posing a serious global health threat. The demand for novel therapeutic strategies has become increasingly important, given that conventional options may be inaccessible and costly, and are often associated with side effects, hampering patient compliance. The scientific validation of alternative strategies, such as phytotherapy has, therefore, become a major focus in the treatment and management of hypertension, as it is perceived as being cheap, accessible, and possessing minimal side effects. Hence the investigation of medicinal plants, within the field of novel drug discovery, is of interest as plants possess various phytochemicals displaying biological activities, which may be beneficial in hypertension, and it’s associated complications. Since there is no existing scientific data available to validate its medicinal usage, this study, therefore, evaluated the in vitro and in vivo antihypertensive effects of Tulbaghia acutiloba. The hydro-methanolic extracts of the plant parts (i.e. leaves, flowers, rhizomes and roots) were initially evaluated in vitro for their phytochemistry, antioxidant potential, angiotensin-converting enzyme (ACEI) inhibition activities, and heavy metal content. The phytochemical investigation of the various parts of the plants showed the presence of phenols, amino acids and alkaloids in all parts, with the leaves exhibiting a higher total phenolic content, in comparison to the other parts. Further analysis, using gas chromatography–mass spectrometry (GC-MS), revealed the presence of bioactive compounds, such as α-linolenic acid, which was found only in the leaves. Other compounds such as oleic acid and palmitic acid were found in all the parts of the plants. All parts of the plant showed antioxidant activity in vitro. Heavy metal toxicity analysis revealed the safety profile for all parts of the plants. All parts also showed a potential ACE inhibitory effect of greater than 50%, with the leaves showing the most significant effects, comparable to the conventional drug, Ramipril. We further investigated the effect of the hydro-methanolic leaf extract on oxidative stress, endothelial function, cardiovascular, renal and haematological parameters, associated with hypertension, in an L-NAME induced hypertensive rat model. The administration of the hydro-methanolic leaf extract of Tulbaghia acutiloba at different concentrations of 40, 60 and 80mg/kg b.w., reduced systolic, diastolic and mean arterial pressure in the model, with a pronounced effect at the dosage of 80mg/kg b.w. Additionally, the leaves of T. acutiloba significantly enhanced bradykinin receptor levels (B1 and B2), nitric oxide (NO) availability, promoted antioxidant activities and significantly reduced ACE activity in serum and cardiac tissues in hypertensive rats. Cardioprotection was significantly enhanced at 80mg/kg b.w. of T.acutiloba, as depicted by the cardiac function and morphology, and cardiac gene expression in experimental rats. There was no evidence of toxicity as depicted in the liver enzymatic activity after the administration of T.acutiloba in the hypertensive rats. Administration of T. acutiloba improved renal function as evidenced by the increased creatinine clearance (Ccr), improved fractional excretion of sodium and decreased urine protein-creatinine ratio (UPr/UCr). Additionally, decreased levels of leucocyte infiltration, decrease in both, neutrophil to lymphocyte ratio (NLR) and lymphocyte to monocyte ratio (LMR), was found after administration of T.acutiloba, with a maximal effect occurring at a dose of 80mg/kg b.w. Together, these findings provide scientific validation for T.acutiloba as a medicinal plant that has cardioprotective and antihypertensive properties, and is able to improve renal function and haematological parameters in an L-NAME induced hypertensive rat model. Overall, the data also provides substantive evidence for the possible usage of T.acutiloba as an alternate antihypertensive agent, in resource limited areas where conventional drugs are inaccessible. Key Words: Tulbaghia acutiloba, phytotherapy, cardioprotection, L-NAME, renal function, haematology.
Investigating the biomarker potential of exosomes in preeclampsia.
(2019) Pillay, Preenan.; Mackraj, Irene.
Preeclampsia is a hypertensive disorder of pregnancy and one of the leading causes of maternal and perinatal morbidity, affecting up to 7 -10% of pregnancies globally which results in 50 000-76 000 maternal deaths per year worldwide. Preeclampsia remains an enigmatic phenomenon due to its unknown etiology. This is attributed to its multifactorial nature, which complicates clinical diagnosis and management, hence the need for a definitive biomarker. Several candidate biomarkers of preeclampsia have been identified but none have the potential to diagnose preeclampsia in early pregnancy. Exosomes have recently emerged as promising biomarkers of the disease and the present study, therefore, focuses on determining the context of the use of exosomes as biomarkers of preeclampsia. In our approach, we developed a theoretical framework for the evaluation of exosomes as potential biomarkers of preeclampsia in terms of the specified criteria defined by the Food & Drug Administration (US) (FDA) Biomarker Workgroup. This subsequently led to the evaluation of the context of use of exosomes as biomarkers of preeclampsia by determining the role of exosomal microRNA in the pathophysiology of preeclampsia using direct digital detection, computational algorithms and biological databases. We identified distinct exosomal miRNAs signatures involved in the aberrant pathophysiology of preeclampsia which serve as promising biomarkers. Furthermore, in terms of the FDA criteria, it is important to incorporate the intent-to-diagnose preeclampsia in combination with comorbidities associated with the increased susceptibility/risk of preeclampsia. It is clinically evident that HIV-positive pregnant women on (Highly Active Antiretroviral Therapy) HAART are at a greater risk of developing preeclampsia due to an unknown immune-related pathology caused by HAART. We, therefore, determined the potential diagnostic application of exosomal cytokines in preeclamptic and HIV-positive preeclamptic women on HAART. In doing so we have identified altered exosomal cytokine levels in both preeclampsia and HIV-positive pregnant women, which suggests an aberrant mechanism of exosomal cytokine encapsulation, which modulates immune responses in both disease states. Importantly, we show that exosomal Tumor necrosis factor alpha (TNF-α) may have clinical validity in diagnosing preeclampsia and preeclampsia in HIV-infected pregnant women. Abstract (isiZulu) I-preeclampsia iyinkinga ephezulu yokukhulelwa kanye neyodwa yezimbangela ezibangela ukugula komama nokubeletha, okuphazamisa ama-7 -10% wezokukhulelwa emhlabeni wonke okuholela ekufeni kwabantu abangu-50 000-76 000 emhlabeni wonke. I-preeclampsia iyisici esiyinkimbinkimbi ngenxa ye-etiology engaziwayo. Lokhu kubangelwa uhlobo olunezinhlobonhlobo zezinto ezihlukahlukene, okubandakanya ukuxilongwa nokuphathwa kwemitholampilo, ngakho-ke isidingo se-biomarker ecacile. Kunezimboni eziningana zepreeclampsia ezikhethwe yi-candidate kodwa azikho ongakwazi ukuhlolisisa i-preeclampsia ekukhulelwe kokuqala. Ama-Exosome asanda kuvela njengezicikumezi ezithembisayo zesifo futhi isifundo samanje, sigxile ekunqumeni umongo wokusetshenziswa kwama-exosomes njengama-biomarkers we-preeclampsia. Endleleni yethu, sathuthukisa uhlaka lwezinhlelo zokuhlola ama-exosomes njengama-biomarkers angaba yi-preeclampsia ngokwemigomo ebekiwe echazwe yi-Food & Drug Administration (US) (FDA) Biomarker Workgroup. Lokhu kwaholela ekuhlolweni kokusetshenziswa kwama-exosomes njengama-biomarkers of preeclampsia ngokunquma indima ye-exosomal microRNA ekuziphatheni kwe-preeclampsia esebenzisa ngokuqondile ukutholakala kwedatha, ukuhlelwa kwezinto zokusebenzisa izibalo kanye nolwazi lwezinto eziphilayo. Sithole amasignesha ama-miRNA ahlukile asebenzayo kuperosis of preeclampsia esebenza njengama-biomarkers athembisayo. Ngaphezu kwalokho, ngokwemigomo ye-FDA kubalulekile ukufaka i-preeclampsia ye-inten-to-diagnostic ngokubambisana nama-comorbidities ehambisana nokwehluleka / ukulimala kwepreeclampsia. Kuyabonakala emitholampilo ukuthi abesifazane abane-HIV abakhulelwe (i-Highly Active Antiretroviral Therapy) i-HAART ingengozini enkulu yokuthuthukisa ipreeclampsia ngenxa yokugula okungaziwa komzimba okubangelwa i-HAART. Ngakho-ke, sinquma ukuthi kungenzeka yini ukuhlolwa kwesifo se-cytokines exosomal ku-preeclamptic nakwabesifazane abane-HIV ngaphambili kwe-HAART. Ngokwenza kanjalo sesiye sabona amazinga e-cytokine ashintshiwe eguquguqukayo kokubili preeclampsia nabesifazane abakhulelwe abane-HIV, okusikisela indlela engavamile yokukhipha i-exosomal cytokine encapsulation, eyenza ukuthi izimpendulo zamasosha omzimba zisetshenziswe. Okubaluleke kakhulu, sibonisa ukuthi i-tumor necrosis factor alpha (TNF-α) ingaba nokusebenza komtholampilo ekuhloleni i-preeclampsia kanye ne-preeclampsia kwabesifazane abakhulelwe abane-HIV.
The optimisation of a preeclampsia-like L-NAME rat model : a focus on utero-placental dysfunction.
(2014) Soobryan, Nerolen.; Mackraj, Irene.
Preeclampsia is a multi-system pregnancy syndrome characterized by the sudden onset of hypertension, escalated proteinuria and in some cases oedema usually after 20 weeks of gestation. Preeclampsia is further categorized as a two stage disorder namely; early and late onset. This study was aimed at developing a rat model that will mimic the classic clinical symptoms in preeclampsia through chronic administration of Nitro–L-Arginine Methyl Ester (L-NAME), and investigated whether Sildenafil Citrate (ViagraTM) (SC) aided in alleviating these symptoms. One hundred and twenty adult nulliparous pregnant female Sprague Dawley rats were used for the study. These were divided into five groups; the pregnant control, early and late onset and respective ViagraTM treated animals. On gestational day 12 and 19 as well as after delivery, physiological parameters such as blood pressure, proteinuria, urine volume, foetal body weight and number of live pups were taken. Post sacrifice and tissue harvesting, various histological, biochemical and gene expression analyses were done. The identification of probable early and late onset biomarkers to characterize preeclampsia was investigated (Ethics number: 047/12/Animal). We found that the administration of L-NAME during the pregnancy created a preeclamptic like syndrome. SC treated rats showed improved foetal and maternal parameters compared to their respective preeclamptic group. The results of this study support angiogenic, antiangiogenic and inflammatory markers as possible biomarkers for preeclampsia. Further studies using our model and in vitro studies, can help to clarify key questions; such as when exactly does remodelling of the spiral arteries occur, as well as the early detection of this disorder. This study which focuses on the optimisation of an animal model is of great interest to clinicians who do not have a biomarker for the early onset of preeclampsia.
Quantification of circulating cell free fetal DNA and cell free total DNA in normal pregnancy and in pregnancy-related hypertension in Black South African Women.
(2016) Eche, Simeon.; Mackraj, Irene.; Moodley, Jagidesa.
Abstract available in PDF file.
Renal and metabolic effects of tulbaghia violacea harv. and captopril in fructose-fed streptozotocin induced diabetic rats.
(2017) Joseph, Kimane Megan.; Mackraj, Irene.; Moodley, Kogilambal.
Background: Diabetes mellitus has rapidly emerged as a worldwide epidemic resulting in significant morbidity and mortality. The incidence of type 2 diabetes mellitus, induced by a high carbohydrate diet, a sedentary lifestyle as well as obesity, is increasing rapidly. Despite the availability of current conventional drugs, the complications of diabetes mellitus continue to progress. Therefore the search for alternate therapies that are antidiabetic in nature and elicit minimal side effects is essential. This study investigated the effects of the medicinal plant Tulbaghia violacea. Harv and angiotensin converting enzyme inhibitor, Captopril in a fructose-fed streptozotocin induced diabetic rat model. Methods: Thirty-six, male Sprague-Dawley rats (six-week old) were randomly divided into six groups’ namely non-diabetic control, diabetic control, diabetic treated with Tulbaghia violacea Harv. (60 mg/kg bw), diabetic treated with captopril (50 mg/kg bw), diabetic treated with metformin (250 mg/kg bw) and diabetic treated with glibenclamide (10 mg/kg bw). Diabetes was induced by fructose feeding for 1 week followed by a single intraperitoneal injection of 40 mg/kg.bw streptozotocin. Animals with a fasting blood glucose concentration >25mmol/L were considered diabetic and included in the study. Thereafter, respective doses of Tulbaghia violacea and conventional drugs were daily administered to the diabetic groups by oral gavage for seven weeks. At week six, an oral glucose tolerance test was performed. At the end of week 7, the animals were euthanized by halothane overdose. Blood was collected and organs were harvested for further biochemical analyses. Results: Tulbaghia violacea treatment significantly increased plasma insulin and liver glycogen content. Tulbaghia violacea treatment also reduced liver thiobarbituric acid reactive substances levels, increased liver superoxide dismutase concentration and increased plasma nitric oxide levels. Furthermore, Tulbaghia violacea administration reduced serum triglycerides, total cholesterol, VLDL cholesterol, LDL cholesterol and increased HDL cholesterol. The plant treated group showed increased pancreatic islet counts as well as improved glomerular morphology. The angiotensin converting enzyme inhibitor captopril showed a significant increase in angiotensin converting enzymeactivity as well as increased angiotensin type 1 receptor expression compared to the diabetic controls and Tulbaghia violacea. Conclusion: Tulbaghia violacea did not decrease fasting blood glucose levels or improve glucose tolerance. However, in this study, the data obtained demonstrated the ability of Tulbaghia violacea to elicit antioxidant and hypolipidemic effects, augment plasma insulin levels, improve pancreatic and glomerular morphology and positively impact β- cell function in a fructose-fed streptozotocin induced diabetic rat model.
Respiratory patterns and cytokine profiles among recreational athletes and a sedentary group.
(2021) Padayachee, Joel.; Mackraj, Irene.; Moodley, Kogie.
Background: An increasing trend in sedentary lifestyles and physical inactivity has contributed to a higher incidence of obesity, a major health concern. Despite the fact that a sedentary lifestyle poses a considerable health risk and contributes to the prevalence of various diseases, sedentary populations are reluctant to modify health behaviours. An array of behaviour adaption models attest to the importance of knowledge and awareness cues regarding the positive physiological effects of exercise when addressing behaviour modification. Within this context, the cross-sectional study intends to describe the physiological effects of three recreational sport disciplines and one sedentary group on respiratory patterns and cytokine profiles within a South African cohort as a means to create knowledge and awareness cues for a sedentary population. Methods: The sample for the study comprising four sub-groups (swim-20, soccer-20, volleyball-20, sedentary-20) included 80 participants. Standardized anthropometric techniques were used to complete height (metres), weight (kilograms) and BMI measurements. The spirometry measurements were performed in accordance with the American Thoracic Society (ATS) recommendations using a MIR SPIROLAB II spirometer. The cytokine measurements were completed using the Beckman Coulter Access Immuno-Assay South African Manufacturer Kit as per the commercial laboratory recommendation. Data was analysed with IBM Statistical Package for Social Sciences version 27 (Chicago IL, USA). Results and Discussion: The respiratory patterns in the swim, soccer and volleyball sport groups were significantly different (p<0.01). All the recreational sport groups had significantly increased lung parameters compared to the sedentary group (p<0.01). The cytokine expression for the swim, soccer, volleyball and sedentary groups were significantly different (p<0.01). Conclusion: The findings of the study support the use of recreational swimming as a means to reduce obesity caused by sedentary lifestyles which has been identified as a global problem. Swimming is also beneficial for improving respiratory patterns over and above the soccer and volleyball group which is beneficial for the management of restrictive lung conditions. The cytokine expression differed in the recreational sport groups. Recreational swimming, soccer and volleyball support low levels of systemic inflammation but studies with larger samples are required to corroborate the findings, in terms of the influence of cytokine levels on spirometry values.
The role of endoplasmic reticulum stress in shedding of syncytiotrophoblast microparticles in pregnant black South African women.
(2016) Verma, Sonal Raj.; Mackraj, Irene.
Background and aim: Preeclampsia, accounts for the majority of maternal deaths emanating from hypertension in pregnancy. Although its exact aetiology is unclear, endoplasmic reticulum (ER) stress and trophoblast apoptosis are implicated. The placental microenvironment in preeclampsia is hypoxic and induces the expression of Hypoxia inducible factor-1 alpha (HIF-1 α) and CHOP (C/EBP homologous protein) which are activated due to ER stress. Hypoxia-induced oxidative and endoplasmic reticulum stress initiate a cascade of apoptotic events with the consequential shedding of microparticles which mediate the peripheral maternal syndrome of preeclampsia. The main aim of the study was to immuno-localise the expression of HIF-1 α and CHOP in placental tissues and concomitantly characterise and quantify the syncytiotrophoblast microparticles in the maternal circulation. Materials and Methods: Plasma and placental tissue were obtained from normotensive and pre-eclamptic pregnant women. The expression of HIF-1α and CHOP was analysed using immunohistochemistry. Microvesicles in maternal circulation were isolated and their size distribution was determined using nanoparticle tracking analysis. The relative concentration of syncytiotrophoblast microvesicles (STBMs) from isolated microvesicles was determined using Placental Alkaline Phosphatase ELISA. Results: This study demonstrated an increased immuno-expression of HIF-1 α and CHOPS in preeclampsia compared to the controls (p < 0.05). Additionally, a significant increase in the mean syncytiotrophoblast microparticles concentration was observed in PE, compared to the controls (p < 0.05). Further analysis showed a positive correlation between the immunohistochemical expression of HIF-1 α and CHOP and the STBMs concentration. Conclusion: This study demonstrates increased placental-expression of HIF-1α and CHOP in preeclampsia compared to normotensive pregnancies which directly relate to the increase syncytiotrophoblast microvesicles concentration in maternal circulation. These findings indicate that placental hypoxia and ER stress are contributory factors to the pathogenesis of PE and may be a key contributory factor in placental cell apoptosis and the consequent release of placental derived debris into the maternal circulation. Key words: HIF-1α; CHOP; Syncytiotrophoblast Microvesicles; Pre- eclampsia; Endoplasmic Reticulum Stress; Hypoxia
The role of mir-29a, mir-181a, and mir-222 in preeclamptic and gestational hypertensive patients.
(2017) Khaliq, Olive Pearl.; Mackraj, Irene.
Backgrounds Hypertensive disorders of pregnancy, a major cause of maternal and neonatal morbidity worldwide are characterized by widespread maternal endothelial dysfunction and metabolic disorders (blood pressure and insulin resistance). Dysregulation in proteins (AKT and PI3K) involved in the insulin signaling pathway lead to insulin resistance, which is a common feature in the second half of most pregnancies complicated by preeclampsia and gestational hypertension. The objective of this study was to quantify microRNAs in serum and placental tissue of women with gestational hypertension (GH) and preeclampsia (PE). Methods This study is a prospective cross-sectional study involving 32 normotensive pregnant women (control), 32 women with preeclampsia (PE) and 28 with gestational hypertension (GH). The patients were recruited from a regional hospital in Durban, KwaZulu-Natal Province, South Africa. Serum and placental microRNA were quantified using RT-qPCR to compare levels of expression in the control, PE, and GH. In addition, a western blot analysis was carried out to investigate the levels of protein expression (AKT and PI3K) in the insulin signaling pathway. Results Serum, miRNA-222 quantitative real-time PCR expression levels were significantly lower in PE compared to normotensives (p=0.0186). miR-29 expression levels were significantly higher in PE (p<0.0001) and GH (p<0.0001) groups compared to normotensives. miR-181a serum expression levels of GH were significantly higher compared to normotensives (p=0.0070). Placental tissue expression showed significantly higher expression levels of miR-181a in PE (p=0.0344) and GH (p=0.0344) groups compared to normal controls. Western blot analysis of proteins showed a lower expression of AKT-serine and threonine in the PE (p=0.0001) compared to the normal control groups and significantly higher expression in the GH (p=0.0001) groups compared to the normal controls. Furthermore, the expression of the phosphatidyl-inositol-3 kinase (PI3K) was statistically lower in PE (p=0.0001) and GH (p=0.0001) compared to the normal controls. Discussion/Conclusion MicroRNAs may be used as potential biomarkers for PE and GH. The results of this study showed a correlation between the expression levels of miRNAs with AKT/PI3K in the insulin signaling pathway, reinforcing the existence of metabolic dysregulation in PE and GH