Comparative analysis of MTP -493G/T and ABCG2 34G/A polymorphisms and theirs expression in HIV-associated lipodystrophy patients

HIV-associated lipodystrophy (HIVLD) is a metabolic condition with an irregularity in the production of lipoprotein particles, and its occurrence varies among HIV-infected patients. MTP and ABCG2 genes have a role in the transport of lipoproteins. The polymorphisms of MTP -493G/T and ABCG2 34G/A affect its expression and influence the secretion and transportation of lipoproteins. Hence, we investigated the MTP -493G/T and ABCG2 34G/A polymorphisms in 187 HIV-infected patients (64 with HIVLD and 123 without HIVLD) along with 139 healthy controls using polymerase chain reaction (PCR)-restriction fragment length polymorphism and expression analysis using real-time PCR. ABCG2 34A allele showed an insignificantly reduced risk of LDHIV severity [P = 0.07, odds ratio (OR) = 0.55]. MTP -493T allele exhibited a non-significantly reduced risk for the development of dyslipidemia (P = 0.08, OR = 0.71). In patients with HIVLD, the ABCG2 34GA genotype was linked with impaired low-density lipoprotein levels and showed a reduced risk for LDHIV severity (P = 0.04, OR = 0.17). In patients without HIVLD, the ABCG2 34GA genotype was associated with impaired triglyceride levels with marginal significance and showed an increased risk for the development of dyslipidemia (P = 0.07, OR = 2.76). The expression level of MTP gene was 1.22-fold decreased in patients without HIVLD compared with that in patients with HIVLD. ABCG2 gene was upregulated 2.16-fold in patients with HIVLD than in patients without HIVLD. In conclusion, MTP -493C/T polymorphism influences the expression level of MTP in patients without HIVLD. Individuals without HIVLD having ABCG2 34GA genotype with impaired triglyceride levels may facilitate dyslipidemia risk

Poly ADP-Ribose Polymerase-1 inhibition by 3-aminobenzamide recuperates HEI-OC1 auditory hair cells from blast overpressure-induced cell death

Introduction: Poly ADP-Ribose Polymerase-1 (PARP1), a DNA repair enzyme is implicated as a key molecule in the pathogenesis of several neurodegenerative disorders. Traumatic insults inducing oxidative stress results in its over-activation causing inflammation and cell death (Parthanatos). As PARP1 inhibition is known to reduce oxidative stress, we hypothesized that PARP1 inhibition by a known inhibitor 3-aminobenzamide (3AB) might recuperate the damage in an in vitro model of blast injury using HEI-OC1 cells (mouse auditory hair cells).Methods: Here, we evaluated the protective effect of 3AB on HEI-OC1 cells following single and repetitive blast overpressures (BOPs).Results: We found that inhibition of PARP1 b 3AB inhibits the PARP1 enzyme and its action of a post-translational modification i.e. formation of Poly ADP-Ribose Polymers which leads to massive ATP depletion. PARP inhibition (3AB treatment) reduced the oxidative stress (4HNE, a marker of lipid peroxidation, and 8OHdG, a marker of oxidative DNA damage) in cells exposed to single/repetitive BOPS through up-regulation of Nrf2, a transcriptional regulator of antioxidant defense and the GCLC, a rate limiting enzyme in the synthesis of glutathione.Discussion: Overall, we found that PARP inhibition by 3AB helps to maintain the viability of BOP-exposed auditory hair cells by recuperating the ATP pool from both mitochondrial and glycolytic sources.</jats:p

Vestibular Cochlear Manifestations in COVID-19 Cases

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a high transmissible infectious disease that primarily impacts the respiratory system and leads to death as it worsens. Ever since the World Health Organization declared the disease as a global pandemic, the pathophysiology, clinical manifestations, and disease prognosis has been discussed in various literature. In addition to impaired respiratory health, the symptoms also indicated the involvement of the cardiovascular and neurological system after SARS-CoV-2 infection. Despite the pulmonary, cardiovascular, and neurological complications, many reports also revealed the prevalence of vestibulocochlear symptoms like dizziness, vertigo, vestibular neuritis, sudden sensorineural hearing loss, and tinnitus. Though many clinical reports and scientific reviews reported the vestibular and cochlear impairments associated with coronavirus disease 2019 (COVID-19) infection, the underlying pathological mechanisms are still unclear and unexplored. In this review, we discussed the published clinical reports, research articles, and literature reviews related to vestibulocochlear manifestations following SARS-CoV-2 infections. We also summarized the current knowledge about the prevalence, epidemiological and clinical features, and potential pathological mechanisms related to vestibular and cochlear manifestations resulting from COVID-19 infections.</jats:p

Role of APOC3 3238C/G, APOB 12669G/A and SCARB1 1050C/T polymorphisms, their expression in patients of HIV-associated lipodystrophy

Apolipoproteins and Scavenger Receptor Class B1 (SCARB1) proteins are involved in the etiology of HIV-associated lipodystrophy (HIVLD). APOC3 3238C/G, APOB 12669G/A and SCARB1 1050C/T polymorphisms were linked with increased level of APOB, TG, HDL-C and risk of cardiovascular diseases (CVDs). Hence, we evaluated the genetic variations of APOC3 3238C/G, APOB 12669G/A and SCARB1 1050C/T in 187 patients of HIV (64 with HIVLD, 123 without HIVLD) and 139 healthy controls using PCR-RFLP and expression by qPCR. The genotypes of SCARB1 1050 TT and APOB 12669AA showed a risk to severe HIVLD (P = 0.23, OR = 4.95; P = 0.16, OR = 2.02). The APOC3 3238 GG genotype was associated with a lesser risk of severe HIVLD (P = 0.07, OR = 0.22). The APOB 12669 GA genotype was associated with a greater risk of HIVLD severity in patients with impaired LDL, triglyceride (TG), and cholesterol levels (P = 0.34, OR = 4.13; P = 0.25, OR = 3.64; P = 0.26, OR = 5.47). Similarly, APOB 12669AA genotypes in the presence of impaired triglyceride levels displayed the susceptibility to severity of HIVLD (P = 0.77, OR = 2.91). APOB 12669 GA genotype along with impaired HDL and cholesterol levels indicated an increased risk for HIVLD acquisition among patients without HIVLD (P = 0.42, OR = 2.42; P = 0.26, OR = 2.27). In patients with and without HIVLD, APOC3 3238CG genotypes having impaired cholesterol and glucose levels had higher risk for severity and development of HIVLD (P = 0.13, OR = 2.84, P = 0.34, OR = 1.58; P = 0.71, OR = 1.86; P = 0.14, OR = 2.30). An increased expression of APOB and SCARB1 genes were observed in patients with HIVLD (+0.51 vs. −0.93; +4.78 vs. +3.29), and decreased expression of APOC3 gene was observed in patients with HIVLD (−0.35 vs. −1.65). In conclusion, the polymorphisms mentioned above were not associated with the modulation of HIVLD. However, in the presence of impaired triglyceride, HDL, cholesterol and glucose levels, APOB 12669AA and 12669 GA, APOC3 3238CG genotypes indicated a risk for the development and severity of HIVLD

Selective Deletion of NBCe1 in Reactive Astrocytes Attenuates Ischemic Stroke Brain Damage

The electrogenic sodium bicarbonate transporter 1 (NBCe1/Slc4a4), predominantly expressed in astrocytes, is important for brain pH regulation and homeostasis. Increased NBCe1 expression in reactive astrocytes has been associated with neuronal degeneration in ischemic stroke. However, the effects of astrocytic NBCe1 inhibition in stroke remain contradictory, and the underlying mechanisms are unclear. Here, we show that wild‐type (WT) mice exhibited elevated NBCe1 expression in the peri‐lesional regions at 3 days post‐stroke. Astrocytic Nbce1 gene deletion in inducible Gfap‐CreERT2+/−; Nbce1f/f mice (Nbce1iΔAstro) resulted in a significant reduction in NBCe1 mRNA and protein expression in astrocytes. Compared to WT stroke mice, Nbce1iΔAstro mice displayed reduced infarct volume, decreased brain swelling, improved cerebral blood flow, and accelerated neurological function recovery in the 1–5‐day acute post‐stroke period. Moreover, Nbce1iΔAstro stroke mice exhibited decreased blood–brain barrier (BBB) permeability, accompanied by preserved perivascular AQP4 polarization, upregulation of Kir4.1 protein expression, and reduced astrocyte domain volume. Importantly, Nbce1iΔAstro stroke brains revealed an anti‐inflammatory cytokine profiling signature, marked by increased TIMP‐1 expression. Together, our findings suggest that astrocytic upregulation of pH regulatory protein NBCe1 after stroke contributes to increased BBB permeability, reactive astrogliosis, inflammation, and perivascular AQP4 dysregulation. Targeting astrocytic NBCe1 may represent a promising new therapeutic strategy to mitigate astroglial dysfunction in the post‐stroke brain