Sphingolipid metabolism cooperates with BAK and BAX to promote the mitochondrial pathway of apoptosis.

Mitochondria are functionally and physically associated with heterotypic membranes, yet little is known about how these interactions impact mitochondrial outer-membrane permeabilization (MOMP) and apoptosis. We observed that dissociation of heterotypic membranes from mitochondria inhibited BAK/BAX-dependent cytochrome c (cyto c) release. Biochemical purification of neutral sphingomyelinases that correlated with MOMP sensitization suggested that sphingolipid metabolism coordinates BAK/BAX activation. Using purified lipids and enzymes, sensitivity to MOMP was achieved by in vitro reconstitution of the sphingolipid metabolic pathway. Sphingolipid metabolism inhibitors blocked MOMP from heavy membrane preparations but failed to influence MOMP in the presence of sphingolipid-reconstituted, purified mitochondria. Furthermore, the sphingolipid products, sphingosine-1-PO(4) and hexadecenal, cooperated specifically with BAK and BAX, respectively. Sphingolipid metabolism was also required for cellular responses to apoptosis. Our studies suggest that BAK/BAX activation and apoptosis are coordinated through BH3-only proteins and a specific lipid milieu that is maintained by heterotypic membrane-mitochondrial interactions.

B cell lymphoma-2 (BCL-2) homology domain 3 (BH3) mimetics demonstrate differential activities dependent upon the functional repertoire of pro- and anti-apoptotic BCL-2 family proteins.

The B cell lymphoma-2 (BCL-2) family is the key mediator of cellular sensitivity to apoptosis during pharmacological interventions for numerous human pathologies, including cancer. There is tremendous interest to understand how the proapoptotic BCL-2 effector members (e.g. BCL-2-associated X protein, BAX) cooperate with the BCL-2 homology domain only (BH3-only) subclass (e.g. BCL-2 interacting mediator of death, BIM; BCL-2 interacting-domain death agonist, BID) to induce mitochondrial outer membrane permeabilization (MOMP) and apoptosis and whether these mechanisms may be pharmacologically exploited to enhance the killing of cancer cells. Indeed, small molecule inhibitors of the anti-apoptotic BCL-2 family members have been designed rationally. However, the success of these "BH3 mimetics" in the clinic has been limited, likely due to an incomplete understanding of how these drugs function in the presence of multiple BCL-2 family members. To increase our mechanistic understanding of how BH3 mimetics cooperate with multiple BCL-2 family members in vitro, we directly compared the activity of several BH3-mimetic compounds (i.e. ABT-263, ABT-737, GX15-070, HA14.1, TW-37) in biochemically defined large unilamellar vesicle model systems that faithfully recapitulate BAX-dependent mitochondrial outer membrane permeabilization. Our investigations revealed that the presence of BAX, BID, and BIM differentially regulated the ability of BH3 mimetics to derepress proapoptotic molecules from anti-apoptotic proteins. Using mitochondria loaded with fluorescent BH3 peptides and cells treated with inducers of cell death, these differences were supported. Together, these data suggest that although the presence of anti-apoptotic BCL-2 proteins primarily dictates cellular sensitivity to BH3 mimetics, additional specificity is conferred by proapoptotic BCL-2 proteins.

Poor Glycemic Control Affecting Screening of Prostate Carcinoma.

Introduction Diabetes and cancer are commonly linked together. The possible links include insulin resistance, hyperinsulinemia, hyperglycemia, oxidative stress, and chronic inflammation. These are factors that have potential promoting effects on the progression of cancer in many ways. Measurement of prostate-specific antigen (PSA) is widely applied for early detection of prostate cancer. However, several factors influence serum PSA levels in men including age, benign prostatic hyperplasia, prostatitis, and body mass index (BMI). The risk of several malignancies is increased in diabetes but the risk of prostate carcinoma in diabetic patients is reduced secondary to lowering of testosterone levels during the state of hyperinsulinemia. A negative association between serum PSA levels and metformin use is also an explanation of low cancer prostate incidence with diabetes. Objective The study aims to evaluate the PSA levels in diabetic patients with poor glycemic control i.e., glycated hemoglobin (HbA1c) ≥ 7%) vs good glycemic control (HbA1c < 7%). Materials and methods Samples of PSA in diabetic patients collected in the Department of Biochemistry at Indira Gandhi Institute of Medical Sciences (IGIMS), Patna, were included. The observational study was carried out on clinically diagnosed 318 cases of diabetes attending both the outpatient and inpatient Department, IGIMS, Patna. Six ml venous blood samples were collected from patients after obtaining informed consent and ethical clearance. Patient details regarding age, complete clinical details, and general physical examinations were recorded. Serum levels of PSA, fasting plasma glucose (FPG) and HbA1c were analyzed and values were compared. The serum level of PSA was estimated by the chemiluminescent immunoassay (CLIA) method on an automated immunoassay analyzer in the Department of Biochemistry, maintaining all the quality control precautions using a control, calibrator, and reagent kit. HbA1c estimation was by chromatography technique. Fasting plasma glucose was estimated using the hexokinase method on an automated chemistry analyzer. Statistical analyses were performed using SPSS software, version 16.0 (SPSS Inc., Chicago). The median and interquartile range were calculated for numerical variables. Covariance analysis was used in the comparisons among groups. The Mann-Whitney U test was applied to detect the comparison between the two groups. Significance was determined by the P value. P value<0.05 was considered significant. Result Serum PSA value was found to be higher in (the good glycemic control group) with a median of 0.99 with an interquartile range of 3.14, than in (the bad glycemic control group) with a median of 0.49 with an interquartile range of 3.9, and the difference is statistically significant. The difference is also statistically significant in the subgroup (i) with PSA value <4 ng/ml. In subgroups (ii) and (iii), PSA values 4 ng/ml-8 ng/ml and PSA values >8 ng/ml respectively, no significant differences were found. Conclusion It was found that serum prostate-specific antigen levels have been lower in diabetic patients with poor glycemic control than in good glycemic control. Future studies with a larger sample size and detailed information on diabetes duration and management are recommended.

Serum Protein Electrophoresis Bands As Biomarkers for Drug-Sensitive Pulmonary Tuberculosis.

INTRODUCTION: India has the highest cases of tuberculosis worldwide. According to WHO (2022), the incidence of tuberculosis in India is 210 per 100,000 population. Their incidence of new positive smear cases is 75 per 100,000 population per year. In tuberculosis, the level of albumin decreases while globulin increases leading to a low albumin to globulin (A/G) ratio, and electrophoresis of serum proteins are good diagnostic approach and provides essential information for monitoring treatment outcomes. MATERIALS AND METHODS: The present study includes 50 cases of pulmonary tuberculosis and 50 age-sex-matched healthy controls. Initially, serum protein estimation and electrophoresis were performed in newly diagnosed patients and controls. All drugs were given as National Tuberculosis Elimination Programme (NTEP) guidelines and blood samples were collected at two-month, four-month, and six-month intervals, and different serum protein fractions were compared and analyzed. RESULTS: The total serum protein was significantly lower in the cases than in the controls; 6.12±0.61 vs. 7.02±0.56 g/dL (p˂0.0020, t-value=3.12). The mean serum albumin was also significantly lower in the cases compared to the controls; 1.65±0.69 vs. 3.87±0.47g/dL (p˂0.0001, t-value=10.98). The α1 globulin started to rise after four months of treatment and at six months level was 0.262±0.32 g/dL. The level of γ globulin continuously decreases after antituberculous treatment to 1.56±0.67 gm/dL at six months. CONCLUSION: The cause of the decrease in total protein and albumin may be due to malnutrition leading to low cellular immunity. Serum protein level and protein electrophoresis should be analyzed as routine tests in patients before, during, and after treatment. It helps us in identifying patients at risk of pulmonary tuberculosis as well prognosis of the disease. This study is a valuable guide in deciding the effective management of tuberculosis patients with drug treatment plans and appropriate dietary intake. Hence, it highlights the complex relationship that exists between poverty and disease.

Vaginal repair of supratrigonal vesicovaginal fistulae--a 10-year review.

INTRODUCTION AND HYPOTHESIS: A 10-year retrospective study was done to determine the outcome of vaginal repair for supratrigonal vesicovaginal fistulae (VVF). METHODS: One hundred thirty-two urinary fistulae were managed from 2001 to 2011 which include 34 ureterovaginal and 98 lower urinary tract fistulae. Fifty-three out of 98 were supratrigonal VVF, 49 were of benign etiology and 4 were malignancy induced. Further analysis of 49 supratrigonal VVF of benign etiology revealed that 38 (77.5%) were of gynecological origin and 11 (22.5%) obstetric. Forty-three were primary and six were recurrent VVF. Thirty (61.2%) supratrigonal VVF were repaired vaginally and 19 (38.8 %) abdominally. Mean follow-up period was 51.7 months. RESULTS: The successful outcome for vaginal and abdominal repair was 86.7% and 100%, respectively (p value = 0.26). Overall, 91.8% supratrigonal VVF were cured at our first attempt. CONCLUSIONS: Majority of supratrigonal VVF can be approached vaginally with success rate comparable to abdominal approach.

Effect of Early Bedside Arm and Leg Cycle Ergometry on Sitting and Standing ability in Hospitalized acute Stroke Patients: A Randomized Controlled Trial.

Objectives: The objective of this study was to evaluate the effect of early bedside arm and leg cycle ergometer exercises as compared to routine physiotherapy on sitting and standing ability in hospitalized acute stroke patients. Materials and Methods: Thirty-four consecutive patients with acute stroke were included in the randomized controlled trial. Patients were divided into two groups based on 1:1 simple randomization Experimental group (n = 18) and control group (n = 16). Experimental Group received arm and leg cycle ergometry along with conventional physiotherapy exercises, while the patients in the control group received conventional physiotherapy exercises. Both the groups received treatment for a total duration of 50 min session, twice a day for 7 days. Preintervention and postintervention measurements were taken for both groups using performance-oriented mobility assessment, postural assessment scale for stroke, Motricity Index, and Trunk control scale. Results: Statistically significant improvement (P < 0.05) was observed in the experimental group and control groupafter intervention among all the outcome measures. Conclusions: Early bedside intervention of cycle ergometer along with routine physiotherapy is effective in improving the sitting and standing abilities, trunk control, and motor function in acute stroke survivors.