A novel mitochondrial DNA variant in MT-ND6: m.14430A>C p.(Trp82Gly) identified in a patient with Leigh syndrome and complex I deficiency.

Leigh syndrome is a severe progressive mitochondrial disorder mainly affecting children under the age of 5 years. It is caused by pathogenic variants in any one of more than 75 known genes in the nuclear or mitochondrial genomes. A 19-week-old male infant presented with lactic acidosis and encephalopathy following a 2-week history of irritability, neuroregression and poor weight gain. He was hypotonic with pathological reflexes, impaired vision, and nystagmus. Brain MRI showed extensive bilateral symmetrical T2 hyperintense lesions in basal ganglia, thalami, and brainstem. Metabolic workup showed elevated serum alanine, and heavy lactic aciduria with increased ketones, fumarate, malate, and alpha-ketoglutarate as well as reduced succinate on urine organic acid analysis. Lactic acidemia persisted, with only a marginally elevated lactate:pyruvate ratio (16.46, ref. 0-10). He demised at age 7 months due to respiratory failure. Exome sequencing followed by virtual gene panel analysis for pyruvate metabolism and mitochondrial defects could not identify any nuclear cause for Leigh syndrome. Mitochondrial DNA (mtDNA) genome sequencing revealed 88% heteroplasmy for a novel variant, NC_012920.1(MT-ND6):m.14430A>C p.(Trp82Gly), in blood DNA. This variant was absent from the unaffected mother's blood, fibroblast, and urine DNA, and detected at a level of 5% in her muscle DNA. Mitochondrial respiratory chain analysis revealed markedly reduced mitochondrial complex I activity in patient fibroblasts (34% of parent and control cells), and reduced NADH-linked respirometry (less than half of parental and control cells), while complex II driven respirometry remained intact. The combined clinical, genetic, and biochemical findings suggest that the novel MT-ND6 variant is the likely cause of Leigh syndrome in this patient. The mitochondrial ND6 protein is a subunit of complex I. An interesting finding was the absence of a significantly elevated lactate:pyruvate ratio in the presence of severe lactatemia, which directed initial diagnostic efforts towards excluding a pyruvate metabolism defect. This case highlights the value of a multidisciplinary approach and complete genetic workup to diagnosing mitochondrial disorders in South African patients.

Composition and distribution of lipoproteins after evolocumab in familial dysbetalipoproteinemia: A randomized controlled trial.

BACKGROUND: Proprotein convertase subtilisin kexin type 9 (PCSK9) monoclonal antibodies (mAbs) reduce fasting and post fat load cholesterol in non-HDL and intermediate density lipoprotein (IDL) in familial dysbetalipoproteinemia (FD). However, the effect of PCSK9 mAbs on the distribution and composition of atherogenic lipoproteins in patients with FD is unknown. OBJECTIVE: To evaluate the effect of the PCSK9 mAb evolocumab added to standard lipid-lowering therapy in patients with FD on fasting and post fat load lipoprotein distribution and composition. METHODS: Randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. Patients received an oral fat load at the start and end of each treatment period. Apolipoproteins (apo) were measured with ultracentrifugation, gradient gel electrophoresis, retinyl palmitate and SDS-PAGE. RESULTS: PCSK9 mAbs significantly reduced particle number of all atherogenic lipoproteins, with a stronger effect on smaller lipoproteins than on larger lipoproteins (e.g. IDL-apoB 49%, 95%confidence interval (CI) 41-59 and very low-density lipoprotein (VLDL)-apoB 33%, 95%CI 16-50). Furthermore, PCSK9 mAbs lowered cholesterol more than triglyceride (TG) in VLDL, IDL and low-density lipoprotein (LDL) (e.g. VLDL-C 48%, 95%CI 29-63%; and VLDL-TG 20%, 95%CI 6.3-41%). PCSK9 mAbs did not affect the post fat load response of chylomicrons. CONCLUSION: PCSK9 mAbs added to standard lipid-lowering therapy in FD patients significantly reduced lipoprotein particle number, in particular the smaller and more cholesterol-rich lipoproteins (i.e. IDL and LDL). PCSK9 mAbs did not affect chylomicron metabolism. It seems likely that the observed effects are achieved by increased hepatic lipoprotein clearance, but the specific working mechanism of PCSK9 mAbs in FD patients remains to be elucidated.

Apolipoprotein E genetic variation, atherogenic index and cardiovascular disease risk assessment in an African population: An analysis of HIV and malaria patients in Ghana.

BACKGROUND: Apolipoprotein E is involved in lipid transport and clearance of lipoprotein through low-density lipoprotein receptors (LDLR). ApoE variation has been linked to cardiovascular disease (CVD) risk. There are 3 isoforms of ApoE which originate from two non-synonymous single nucleotide polymorphisms denoted as ε2, ε3 and ε4. The ε2 isoform is implicated in higher levels of atherogenic lipoprotein with the ε4 isoform causing LDLR downregulation. This leads to variable effects and differential CVD risk. Malaria and HIV are life-threatening diseases affecting several countries globally especially in sub-Saharan Africa. Parasite and viral activities have been implicated in lipid dysregulation leading to dyslipidaemia. This study examined ApoE variation and CVD risk assessment in malaria and HIV patients. METHODS: We compared 76 malaria-only, 33 malaria-HIV coinfected, 21-HIV-only and 31 controls from a tertiary health facility in Ghana. Fasting venous blood samples were taken for ApoE genotyping and lipid measurements. Clinical and laboratory data were collected with ApoE genotyping performed using Iplex Gold microarray and PCR-RFLP. Cardiovascular disease risk was calculated using the Framingham BMI and cholesterol risk and Qrisk3 tools. RESULTS: The frequency of C/C genotype for rs429358 was 9.32%, whiles T/T genotype for rs7412 was found in 2.48% of all participants. ε3/ε3 was the most distributed ApoE genotype accounting for 51.55% of the total participants whiles ε2/ε2 was found in 2.48% of participants, with 1 in malaria-only and 3 in HIV-only patients. There was a significant association between ε4+ and high TG (OR = 0.20, CI; 0.05-0.73; p = 0.015), whiles ε2+ was significantly associated with higher BMI (OR; 0.24, CI; 0.06-0.87; p = 0.030) and higher Castelli Risk Index II in females (OR = 11.26, CI; 1.37-92.30; p = 0.024). A higher proportion of malaria-only participants had a moderate to high 10-year CVD risk. CONCLUSION: Overall malaria patients seem to have a higher CVD risk though the means through which this occurs may be poorly understood. ε2/ε2 genotypes was observed in our population at a lower frequency. Further studies are vital to determine CVD risk in malaria and how this occurs.

Low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol measurement in Familial Dysbetalipoproteinemia.

AIM: To compare LDL-C concentrations using the Friedewald formula, the Martin-Hopkins formula, a direct assay and polyacrylamide gradient gel electrophoresis (PGGE) to the reference standard density gradient ultracentrifugation in patients with Familial Dysbetalipoproteinemia (FD) patients. We also compared non-HDL-cholesterol concentrations by two methods. METHODS: For this study data from 28 patients with genetically confirmed FD from the placebo arm of the EVOLVE-FD trial were used. Four different methods for determining LDL-C were compared with ultracentrifugation. Non-HDL-C was measured with standard assays and compared to ultracentrifugation. Correlation coefficients and Bland-Altman plots were used to compare the methods. RESULTS: Mean age of the 28 FD patients was 62 ± 9 years, 43 % were female and 93 % had an ɛ2ɛ2 genotype. LDL-C determined by Friedewald (R2 = 0.62, p <0.01), Martin-Hopkins (R2 = 0.50, p = 0.01) and the direct assay (R2 = 0.41, p = 0.03) correlated with density gradient ultracentrifugation. However, Bland-Altman plots showed considerable over- or underestimation by the four methods compared to ultracentrifugation. Non-HDL-C showed good correlation and agreement. CONCLUSION: In patients with FD, all four methods investigated over- or underestimated LDL-C concentrations compared with ultracentrifugation. In contrast, standard non-HDL-C assays performed well, emphasizing the use of non-HDL-C in patients with FD.

Effect of evolocumab on fasting and post fat load lipids and lipoproteins in familial dysbetalipoproteinemia.

BACKGROUND: Familial dysbetalipoproteinemia (FD) is the second most common monogenic lipid disorder (prevalence 1 in 850-3500), characterized by postprandial remnant accumulation and associated with increased cardiovascular disease (CVD) risk. Many FD patients do not achieve non-HDL-C treatment goals, indicating the need for additional lipid-lowering treatment options. OBJECTIVES: To evaluate the effect of the PCSK9 monoclonal antibody evolocumab added to standard lipid-lowering therapy on fasting and post fat load lipids and lipoproteins in patients with FD. METHODS: A randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. At the start and end of each treatment period patients received an oral fat load. The primary endpoint was the 8-hour post fat load non-HDL-C area under the curve (AUC). Secondary endpoints included fasting and post fat load lipids and lipoproteins. RESULTS: In total, 28 patients completed the study. Mean age was 62±9 years and 93% had an Ɛ2Ɛ2 genotype. Evolocumab reduced the 8-hour post fat load non-HDL-C AUC with 49% (95%CI 42-55) and apolipoprotein B (apoB) AUC with 47% (95%CI 41-53). Other fasting and absolute post fat load lipids and lipoproteins including triglycerides and remnant-cholesterol were also significantly reduced by evolocumab. However, evolocumab did not have significant effects on the rise above fasting levels that occurred after consumption of the oral fat load. CONCLUSIONS: Evolocumab added to standard lipid-lowering therapy significantly reduced fasting and absolute post fat load concentrations of non-HDL-C, apoB and other atherogenic lipids and lipoproteins in FD patients. The clinically significant decrease in lipids and lipoproteins can be expected to translate into a reduction in CVD risk in these high-risk patients.

Zero malaria: a mirage or reality for populations of sub-Saharan Africa in health transition.

The global burden of malaria continues to be a significant public health concern. Despite advances made in therapeutics for malaria, there continues to be high morbidity and mortality associated with this infectious disease. Sub-Saharan Africa continues to be the most affected by the disease, but unfortunately the region is burdened with indigent health systems. With the recent increase in lifestyle diseases, the region is currently in a health transition, complicating the situation by posing a double challenge to the already ailing health sector. In answer to the continuous challenge of malaria, the African Union has started a "zero malaria starts with me" campaign that seeks to personalize malaria prevention and bring it down to the grass-root level. This review discusses the contribution of sub-Saharan Africa, whose population is in a health transition, to malaria elimination. In addition, the review explores the challenges that health systems in these countries face, that may hinder the attainment of a zero-malaria goal.

A novel description of the Vastus lateralis morphology of the Temminck's ground pangolin (Manis temminckii).

The pangolin (Manidae family) is the world's most trafficked animal, yet very little is known about its physiology and metabolism primarily due to its inconspicuous and solitary nature. Skeletal muscle samples from the Vastus lateralis were collected postmortem from a single female Temminck's ground pangolin (Manis temminckii). Samples were analyzed for fiber type composition, fiber size and myosin heavy chain isoform content. The oxidative and glycolytic metabolic capacity was determined through citrate synthase, 3-hydroxyacetyl co A dehydrogenase, creatine kinase, lactate dehydrogenase, phosphofructokinase and glycogen phosphorylase enzyme activities. Lastly, antioxidant capacity was determined through superoxide dismutase and catalase enzyme activities, and the total antioxidant capacity. The pangolin metabolic profile was then compared to other endurance and nonendurance mammals, in which data were standardized relative to human endurance athletes in order to provide context. Slow twitch type I fibers, rich in mitochondria were the predominant fiber type within the pangolin indicating a reliance on oxidative derived energy from fats and carbohydrates. This suggests that the pangolin has a high endurance capability when compared to other wild animals and human endurance athletes. This is the first study to investigate the skeletal muscle physiology and metabolism of any pangolin species, in an attempt to further understand this endangered animal and aid with conservation efforts.

Chronic and moderate consumption of reduced-alcohol wine confers cardiac benefits in a rat model of pulmonary arterial hypertension.

OBJECTIVES: In pulmonary arterial hypertension (PAH), right ventricular (RV) dysfunction develops via mechanisms involving oxidative stress. Moderate and chronic red wine (RW) consumption reduces oxidative stress and confers cardioprotection but its effect on PAH is unknown. We evaluated whether moderate and chronic consumption of reduced-alcohol RW (RARW) confers cardioprotection in a monocrotaline (MCT)-induced PAH rat model. RESULTS: Rats were randomly grouped: control; MCT; RARW; MCT + RARW. Wine was diluted to mimic moderate intake for humans, and consumed from 7 days before, until 28 days after MCT-injection. Echocardiography measured pulmonary artery acceleration time (PAAT) and RV thickness. Conjugated dienes (CD), and thiobarbituric acid reactive substances (TBARS) concentrations were assessed. MCT induced RV thickness and decreased PAAT compared to controls [1.22 ± 0.09 mm vs 0.46 ± 0.02 mm and 14 ± 1 vs 23 ± 2 m/s, respectively (p < 0.001)]. Chronic RARW consumption limited MCT-induced RV hypertrophy and increased PAAT. CD and TBARS increased in MCT-treated animals compared to controls (672 ± 43 nmol/L vs 453 ± 35 nmol/L; p < 0.01 and 13 ± 2 µmol/L vs 4 ± 0.3 µmol/L; p < 0.01). RARW reduced MCT-induced CD (472 ± 27 nmol/L vs 672 ± 43 nmol/L; p < 0.01). CONCLUSION: Chronic and moderate intake of RARW ameliorates MCT-induced PAH in rats, which may be partly attributable to reduction of lipid peroxidation.

Hyperlipidemic myeloma, a rare form of acquired dysbetalipoproteinemia, in an HIV seropositive African female.

Dysbetalipoproteinemia (DBL) is an uncommon condition characterized by a mixed hyperlipidemia due to accumulation of remnant lipoproteins and is highly atherogenic. Typically, DBL is an autosomal recessive condition requiring an additional metabolic stress with reduced apolipoprotein E (apoE) function. However, DBL is also described in patients with multiple myeloma without the characteristic apoE2/E2 mutation seen in familial DBL. Although the underlying pathogenesis in these cases is not fully characterized, it is thought to occur due to interference with apoE function by antibodies produced from clonal plasma cells. Such cases are referred to as hyperlipidemic myeloma (HLM) and have rarely been described in the literature. To our knowledge there is no prior description of HLM in HIV positive patients in Africa. We describe a case of HLM in an African woman with underlying HIV infection who presented with phenotypic and biochemical features of DBL that responded poorly to lipid lowering therapy.

Novel PCSK9 (Proprotein Convertase Subtilisin Kexin Type 9) Variants in Patients With Familial Hypercholesterolemia From Cape Town.

OBJECTIVE: Familial hypercholesterolemia (FH) is characterized by elevated low-density lipoprotein-cholesterol and markedly increased cardiovascular risk. In patients with a genetic diagnosis, low-density lipoprotein receptor (LDLR) mutations account for >90% of cases, apolipoprotein B (APOB) mutations for ≈5% of cases, while proprotein convertase subtilisin kexin type 9 (PCSK9) gain of function mutations are rare (<1% of cases). We aimed to evaluate the functional impact of several novel PCSK9 variants in a cohort of patients with FH by genetic cascade screening and in vitro functionality assays. Approach and Results: Patients with clinically diagnosed FH underwent genetic analysis of LDLR, and if negative, sequential testing of APOB and PCSK9. We analyzed cosegregation of hypercholesterolemia with novel PCSK9 variants. Gain of function status was determined by in silico analyses and validated by in vitro functionality assays. Among 1055 persons with clinical FH, we identified nonsynonymous PCSK9 variants in 27 (2.6%) patients and 7 of these carried one of the 4 previously reported gain of function variants. In the remaining 20 patients with FH, we identified 7 novel PCSK9 variants. The G516V variant (c.1547G>T) was found in 5 index patients and cascade screening identified 15 additional carriers. Low-density lipoprotein-cholesterol levels were higher in these 15 carriers compared with the 27 noncarriers (236±73 versus 124±35 mg/dL; P<0.001). In vitro studies demonstrated the pathogenicity of the G516V variant. CONCLUSIONS: In our study, 1.14% of cases with clinical FH were clearly attributable to pathogenic variants in PCSK9. Pathogenicity is established beyond doubt for the G516V variant.

Analysis of the regenerative capacity of human serum exosomes after a simple multistep separation from lipoproteins.

Due to the abundance of lipoproteins in blood, it is challenging to characterize the biological functions and components of blood-derived extracellular vesicles. The aim of this study was to develop a multiple-step purification protocol to separate serum exosomes from serum proteins and lipoproteins and assess their regenerative potential. Exosomes were isolated by concentrating them in human serum using ultracentrifugation (UC), followed sequentially by density gradient (DG) UC and size exclusion chromatography (SEC). Purity and characterization were assessed by western blots, Lipoprint®, enzyme-linked immunosorbent assay, electron microscopy, mass spectrometry, and nanoparticle tracking analysis. Functionality was assessed by cell proliferation analysis and with an in vivo subcutaneous angiogenesis model. SEC alone isolated nano-sized vesicles possessing vesicle markers TSG101 and CD9, but there was a substantial presence of apolipoprotein B, predominantly derived from very-low- and intermediate-density lipoprotein particles. This was reduced to an undetectable level using the combined UC DG SEC approach. Mass spectrometry identified 224 proteins in UC DG SEC isolates relative to the 135 from SEC, with considerable increases in exosome-related proteins and reductions in lipoproteins. A consistent but limited increase in human dermal fibroblast proliferation and evidence of neovascularization enhancement were observed after exposure to UC DG SEC exosomes. An UC DG SEC purification protocol considerably improved the removal of lipoproteins during isolation of serum exosomes. The purified exosomes stimulated cell proliferation and potentially increased an in vivo angiogenic response. This multistep purification allows for more accurate identification of serum exosome functional activity and composition.

A Comparison of Hematological, Immunological, and Stress Responses to Capture and Transport in Wild White Rhinoceros Bulls (Ceratotherium simum simum) Supplemented With Azaperone or Midazolam.

Capture and transport are essential procedures for the management and conservation of southern white rhinoceroses (Ceratotherium simum simum), but are associated with stress-induced morbidity and mortality. To improve conservation efforts, it is crucial to understand the pathophysiology of rhinoceros stress responses and investigate drug combinations that could reduce these responses. In this study we measured rhinoceros stress responses to capture and transport by quantifying hematological and immunological changes together with adrenal hormone concentrations. We investigated whether the potent anxiolytic drug midazolam was able to mitigate these responses compared to azaperone, which is more commonly used during rhinoceros transport. Twenty three wild white rhinoceros bulls were transported for 6 h (280 km) within the Kruger National Park for reasons unrelated to this study. Rhinoceroses were immobilized with either etorphine-azaperone (group A, n = 11) or etorphine-midazolam (group M, n = 12) intramuscularly by darting from a helicopter. Azaperone (group A) or midazolam (group M) were re-administered intramuscularly every 2 h during transport. Serial blood samples were collected at capture (TC), the start of transport (T0) and after 6 h of transport (T6). Changes in hematological and immunological variables over time and between groups were compared using general mixed models. Increases in plasma epinephrine and serum cortisol concentrations indicated that rhinoceroses mounted a stress response to capture and transport. Packed cell volume decreased from TC to T6 indicating that stress hemoconcentration occurred at TC. Neutrophils progressively increased and lymphocytes and eosinophils progressively decreased from T0 to T6, resulting in an increase in neutrophil to lymphocyte ratio; a characteristic leukocyte response to circulating glucocorticoids. A reduction in serum iron concentrations may suggest the mounting of an acute phase response. Rhinoceroses experienced a decrease in unsaturated fatty acids and an increase in lipid peroxidation products at capture and toward the end of transport indicating oxidative stress. Midazolam, at the dose used in this study, was not able to mitigate adrenal responses to stress and appeared to directly influence leukocyte responses.

CHALLENGES TO ANIMAL WELFARE ASSOCIATED WITH CAPTURE AND LONG ROAD TRANSPORT IN BOMA-ADAPTED BLACK (DICEROS BICORNIS) AND SEMI-CAPTIVE WHITE (CERATOTHERIUM SIMUM) RHINOCEROSES.

Capture and transport are part of translocation and expose animals to a variety of stressors that can lead to morbidity and mortality. We aimed to establish a better understanding of the physiologic responses to capture and transport in black (Diceros bicornis) and white (Ceratotherium simum) rhinoceroses in Southern Africa. Fourteen adult black rhinoceroses were transported 600 km by vehicle and 32 white rhinoceroses (24 adults and 8 juveniles) were transported 1,300 km by vehicle. The black rhinoceroses had been wild-caught and boma-adapted over 6 wk prior to the translocation and were only sedated to allow for loading into the transport crates. The white rhinoceroses originated from a game farm and were chemically immobilized from a helicopter and then loaded. Paired blood samples were collected from animals at loading (capture) and after transport and evaluated for changes in clinical chemistry analytes, acute phase reactants, and oxidative stress biomarkers. The Wilcoxon rank sum test was used to compare changes in measured analytes from capture and after transport. All rhinoceroses survived capture and transport. Rhinoceroses experienced total body water loss, mobilization of energy reserves, and muscular damage. Alterations in acute phase reactants suggested that animals mounted a stress response. Oxidative stress was observed in black rhinoceroses. We identified the following challenges to animal welfare during transport: hydration status, energy balance, skeletal muscle fatigue, and stress-induced immunomodulation. Measures to mitigate these challenges, such as administration of fluids, need to be included in the planning of future translocations.

Wild antelope skeletal muscle antioxidant enzyme activities do not correlate with muscle fibre type or oxidative metabolism.

Wild antelope are some of the fastest land animals in the world, presenting with high oxidative and glycolytic skeletal muscle metabolism. However, no study has investigated their muscle antioxidant capacity, and may assist in understanding their physical ability and certain pathophysiological manifestations, such as capture myopathy. Therefore, the primary aim of this study was to determine the antioxidant activities superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR), as well as five key regulatory enzymes that serve as markers of glycolysis (phosphofructokinase (PFK) and lactate dehydrogenase (LDH)), the tricarboxylic acid cycle (citrate synthase (CS)), ß-oxidation (3-hydroxyacetyl CoA dehydrogenase (3HAD)) and the phosphagen pathway (creatine kinase (CK)), in the Vastus lateralis muscle of six southern African wild antelope species (mountain reedbuck, springbok, blesbok, fallow deer, black wildebeest and kudu). Four different muscle groups from laboratory rats served as reference values for the enzyme activities. SOD, CS and LDH activities were the highest in the wild antelope, whereas CK appeared highest in rat fast twitch muscles. Between the wild antelope species, differences exist for SOD, CAT, PFK, CK and LDH, but not for CS, 3HAD and GR. CAT and GR correlated positively only with type I fibres. No correlations could be found between muscle fibre type and the oxidative enzymes, CS and 3HAD, from the wild animals, concurring with previous studies on porcine and rats. However, wild antelope and rat muscle CK and SOD strongly correlated, hinting towards an antioxidant role for CK.

Antiretroviral drug-induced endothelial dysfunction is improved by dual PPARα/γ stimulation in obesity.

Obesity rates are rising in HIV-infected populations; however, the putative role of highly active antiretroviral therapy (HAART) in the development of endothelial and cardiovascular derangements in the presence of pre-existing overweight/obesity is unclear. Although dual peroxisome proliferator-activated receptors-alpha/gamma (PPARα/γ) stimulation mitigates HAART-induced metabolic dysfunction, vascular effects are unresolved. To investigate whether HAART induces vascular dysfunction in obesity and to explore the underlying mechanisms of PPARα/γ stimulation, male Wistar rats were placed on a high-calorie diet for 16 weeks. After 10 weeks, HAART (lopinavir/ritonavir, azidothymidine/lamivudine) with/without PPARα/γ agonist, Saroglitazar, was administered daily for six weeks. Excised thoracic aorta rings were subjected to isometric tension studies and Western blot measurements. HAART+Saroglitazar-treated obese animals recorded lower adiposity indices (4.3 ±â€¯0.5%) vs. HAART only-treated obese rats (5.6 ±â€¯0.3%; p < .01). Maximum acetylcholine-induced vasorelaxation (Rmax), was lower in obese+HAART group (76.10 ±â€¯3.58%) vs. obese control (101.40 ±â€¯4.75%; p < .01). However, Rmax was improved in obese+ HAART+Saroglitazar (101.00 ±â€¯3.12%) vs. obese+HAART rats (p < .001). The mean LogEC50 was improved in obese+HAART+Saroglitazar vs. obese+HAART group; p = .003. Improved endothelial function in obese+ HAART+Saroglitazar group was associated with upregulation of eNOS, PKB/Akt and downregulated p22-phox expression vs. obese+HAART group. Therefore, PPARα/γ stimulation attenuated HAART-induced endothelial dysfunction by upregulating vasoprotective eNOS, PKB/Akt signaling and downregulating pro-oxidative p22-phox expression.

Treatment with a fixed dose combination antiretroviral therapy drug containing tenofovir, emtricitabine and efavirenz is associated with cardioprotection in high calorie diet-induced obese rats.

HIV-infection, certain antiretroviral drug classes, especially protease inhibitors (PI), and obesity are associated with increased ischaemic heart disease (IHD) risk. However, the effect of PI-free fixed dose combination (FDC) antiretroviral therapy (ART) on hearts exposed to ischaemia-reperfusion injury (I/R) is unknown, particularly in obesity. This is becoming relevant as World Health Organisation guidelines recommend a FDC ART containing (non-) nucleoside reverse transcriptase inhibitors (tenofovir (TDF), emtricitabine (FTC) and efavirenz (EFV)) as first-line HIV treatment. Additionally, obesity rates are rising in HIV-infected populations, not only in ART-experienced individuals, but also at the time of ART initiation, which may further increase the risk of IHD. Therefore, we investigated the effects of PI-free FDC ART in myocardial I/R-exposed hearts from obese rats. Obesity was induced in male wistar rats via a 16-week high calorie diet. At week 10, treatment with a FDC ART drug containing TDF/FTC/EFV was initiated. Biometric and metabolic parameters, as well as myocardial functional recovery and infract size (IS), and myocardial signalling proteins following I/R were assessed after 16 weeks. Obese rats presented with increased body and intraperitoneal fat mass, elevated triglyceride and TBARS levels, whilst the hearts responded to I/R with impaired functional performance and increased IS. The FDC ART treatment did not alter biometric and metabolic parameters in obese rats. In a novel finding, ART protected obese hearts against I/R as shown by improved functional performance and smaller IS vs. untreated obese hearts. Cardioprotection was underscored by increased myocardial phosphorylated endothelial nitric oxide synthase (eNOS) and reduced AMP-kinase levels. In conclusion, these results demonstrate for the first time, that 6-weeks treatment of obese rats with a FDC ART drug specifically containing TDF/FTC/EFV conferred cardioprotection against I/R. The FDC ART-induced cardioprotection was seemingly unrelated to metabolic changes, but rather due to direct cardiac mechanisms including the up-regulation of myocardial eNOS.

Impact of exercise intensity on oxidative stress and selected metabolic markers in young adults in Ghana.

OBJECTIVE: This study aimed to evaluate the effect of different levels of exercise on markers of oxidative stress and selected metabolic parameters in Ghanaian young adults. RESULTS: Significant increases in a marker of oxidative stress malondialdehyde and antioxidants such as superoxide dismutase and uric acid were observed in the exercisers compared with the inactive group (p < 0.05). Total cholesterol and high density lipoprotein levels were significantly different (p < 0.05) between the two groups. Positive associations between exercise intensity, antioxidant concentration and malondialdehyde were observed within the exercise group for vigorous exercise with regards to uric acid, superoxide dismutase and malondialdehyde (r = 0.512, p = 0.004; r = 0.810, p = 0.001; r = 0.715, p = 0.001) respectively and moderate exercise vs malondialdehyde (r = 0.841, p = 0.001) compared to the inactive group. Exercise participants performed more vigorous exercise (p < 0.001), moderate exercise (p < 0.001) and more walking (p < 0.001) compared with the inactive group while the inactive group exhibited more sitting (p < 0.001). The study provides a first report on the risk associated with increase in oxidative stress and the importance of walking as a health promotion intervention among young Ghanaian adults.

Beneficial Effects of Magnesium Treatment on Heart Rate Variability and Cardiac Ventricular Function in Diabetic Rats.

BACKGROUND: Diabetes mellitus induces life-threatening cardiovascular complications such as cardiac autonomic neuropathy and ventricular dysfunction and is associated with hypomagnesemia. In this study, we investigated the short-term effects of magnesium (Mg2+) treatment on streptozotocin (STZ)-induced diabetic cardiac complications. METHODS: Adult Wistar rats were treated once with STZ (50 mg/kg, intraperitoneally [ip]) or vehicle (citrate) and then daily for 7 days with MgSO4 (270 mg/kg, ip) or saline. On the eighth day, in vivo tail-pulse plethysmography was recorded for heart rate variability (HRV) analysis, and ex vivo Langendorff-based left ventricular (LV) pressure-volume parameters were measured using an intraventricular balloon. Measurements of plasma lipid and Mg2+ levels as well as blood glucose and cardiac tissue Mg2+ levels were also performed. RESULTS: Treatment with Mg2+ prevented diabetes-induced alterations in the standard deviation of the averages of normal-to-normal (NN) intervals (SDANN), root mean square differences of successive NN intervals (RMSSD), heart rate, and low-frequency (LF) power-high-frequency (HF) power ratio. In addition, Mg2+ restored orthostatic stress-induced changes in SDANN, RMSSD, and LF-HF ratio in diabetic rats. In isolated hearts, Mg2+ reversed the diabetes-induced decrease in LV end-diastolic elastance and the right shift of end-diastolic equilibrium volume intercept, without altering LV-developed pressure or end-systolic elastance. However, Mg2+ did not prevent the elevation in blood glucose, total cholesterol, and triglycerides or the decrease in high-density lipoprotein cholesterol in diabetes. Plasma- or cardiac tissue Mg2+ was not different among the treatment groups. CONCLUSION: These results suggest that Mg2+ treatment may attenuate diabetes-induced reduction in HRV and improve LV diastolic distensibility, without preventing hyperglycemia and dyslipidemia. Thus, Mg2+ may have a modulatory role in the early stages of diabetic cardiovascular complications.

Melatonin protects against uric acid-induced mitochondrial dysfunction, oxidative stress, and triglyceride accumulation in C2C12 myotubes.

Excess uric acid has been shown to induce oxidative stress, triglyceride accumulation, and mitochondrial dysfunction in the liver and is an independent predictor of type-2 diabetes. Skeletal muscle plays a dominant role in type 2 diabetes and presents a large surface area to plasma uric acid. However, the effects of uric acid on skeletal muscle are underinvestigated. Our aim was therefore to characterize the effects of excessive uric acid on oxidative stress, triglyceride content, and mitochondrial function in skeletal muscle C2C12 myotubes and assess how these are modulated by the antioxidant molecule melatonin. Differentiated C2C12 myotubes were exposed to 750 µM uric acid or uric acid + 10 nM melatonin for 72 h. Compared with control, uric acid increased triglyceride content by ~237%, oxidative stress by 32%, and antioxidant capacity by 135%. Uric acid also reduced endogenous ROUTINE respiration, complex II-linked oxidative phosphorylation, and electron transfer system capacities. Melatonin counteracted the effects of uric acid without further altering antioxidant capacity. Our data demonstrate that excess uric acid has adverse effects on skeletal muscle similar to those previously reported in hepatocytes and suggest that melatonin at a low physiological concentration of 10 nM may be a possible therapy against some adverse effects of excess uric acid.NEW & NOTEWORTHY Few studies have investigated the effects of uric acid on skeletal muscle. This study shows that hyperuricemia induces mitochondrial dysfunction and triglyceride accumulation in skeletal muscle. The findings may explain why hyperuricemia is an independent predictor of diabetes.

In Vitro Reversible and Time-Dependent CYP450 Inhibition Profiles of Medicinal Herbal Plant Extracts Newbouldia laevis and Cassia abbreviata: Implications for Herb-Drug Interactions.

This study evaluated the effects of Newbouldia laevis and Cassia abbreviata extracts on CYP450 enzyme activity. Recombinant CYP450 enzyme and fluorogenic substrates were used for evaluating inhibition, allowing the assessment of herb-drug interactions (HDI). Phytochemical fingerprinting was performed using UPLC-MS. The herbal extracts were risk ranked for HDI based on the IC50 values determined for each CYP enzyme. Newbouldia laevis inhibited CYP1A2, CYP2C9, and CYP2C19 enzyme activities with Ki of 2.84 µg/mL, 1.55 µg/mL, and 1.23 µg/mL, respectively. N. laevis exhibited a TDI (4.17) effect on CYP1A2 but not CYP2C9 and CYP2C19 enzyme activities. Cassia abbreviata inhibited CYP1A2, CYP2C9, and CYP2C19 enzyme activities showing a Ki of 4.86 µg/mL, 5.98 µg/mL, and 1.58 µg/mL, respectively. TDI potency assessment for Cassia abbreviata showed it as a potential TDI candidate (1.64) for CYP1A2 and CYP2C19 (1.72). UPLC-MS analysis showed that Newbouldia laevis and Cassia abbreviata possess polyphenols that likely give them their therapeutic properties; some of them are likely to be responsible for the observed inhibition. The observations made in this study suggest the potential for these herbal compounds to interact, especially when co-administered with other medications metabolized by these CYP450 enzymes.