Understanding the role of glycation in the pathology of various non-communicable diseases along with novel therapeutic strategies.

Glycation refers to carbonyl group condensation of the reducing sugar with the free amino group of protein, which forms Amadori products and advanced glycation end products (AGEs). These AGEs alter protein structure and function by configuring a negative charge on the positively charged arginine and lysine residues. Glycation plays a vital role in the pathogenesis of metabolic diseases, brain disorders, aging, and gut microbiome dysregulation with the aid of 3 mechanisms: (i) formation of highly reactive metabolic pathway-derived intermediates, which directly affect protein function in cells, (ii) the interaction of AGEs with its associated receptors to create oxidative stress causing the activation of transcription factor NF-κB, and (iii) production of extracellular AGEs hinders interactions between cellular and matrix molecules affecting vascular and neural genesis. Therapeutic strategies are thus required to inhibit glycation at different steps, such as blocking amino and carbonyl groups, Amadori products, AGEs-RAGE interactions, chelating transition metals, scavenging free radicals, and breaking crosslinks formed by AGEs. The present review focused on explicitly elaborating the impact of glycation-influenced molecular mechanisms in developing and treating noncommunicable diseases.

Effect of 12 mg vs 6 mg of Dexamethasone on the Number of Days Alive Without Life Support in Adults With COVID-19 and Severe Hypoxemia: The COVID STEROID 2 Randomized Trial.

Importance: A daily dose with 6 mg of dexamethasone is recommended for up to 10 days in patients with severe and critical COVID-19, but a higher dose may benefit those with more severe disease. Objective: To assess the effects of 12 mg/d vs 6 mg/d of dexamethasone in patients with COVID-19 and severe hypoxemia. Design, Setting, and Participants: A multicenter, randomized clinical trial was conducted between August 2020 and May 2021 at 26 hospitals in Europe and India and included 1000 adults with confirmed COVID-19 requiring at least 10 L/min of oxygen or mechanical ventilation. End of 90-day follow-up was on August 19, 2021. Interventions: Patients were randomized 1:1 to 12 mg/d of intravenous dexamethasone (n = 503) or 6 mg/d of intravenous dexamethasone (n = 497) for up to 10 days. Main Outcomes and Measures: The primary outcome was the number of days alive without life support (invasive mechanical ventilation, circulatory support, or kidney replacement therapy) at 28 days and was adjusted for stratification variables. Of the 8 prespecified secondary outcomes, 5 are included in this analysis (the number of days alive without life support at 90 days, the number of days alive out of the hospital at 90 days, mortality at 28 days and at 90 days, and ≥1 serious adverse reactions at 28 days). Results: Of the 1000 randomized patients, 982 were included (median age, 65 [IQR, 55-73] years; 305 [31%] women) and primary outcome data were available for 971 (491 in the 12 mg of dexamethasone group and 480 in the 6 mg of dexamethasone group). The median number of days alive without life support was 22.0 days (IQR, 6.0-28.0 days) in the 12 mg of dexamethasone group and 20.5 days (IQR, 4.0-28.0 days) in the 6 mg of dexamethasone group (adjusted mean difference, 1.3 days [95% CI, 0-2.6 days]; P = .07). Mortality at 28 days was 27.1% in the 12 mg of dexamethasone group vs 32.3% in the 6 mg of dexamethasone group (adjusted relative risk, 0.86 [99% CI, 0.68-1.08]). Mortality at 90 days was 32.0% in the 12 mg of dexamethasone group vs 37.7% in the 6 mg of dexamethasone group (adjusted relative risk, 0.87 [99% CI, 0.70-1.07]). Serious adverse reactions, including septic shock and invasive fungal infections, occurred in 11.3% in the 12 mg of dexamethasone group vs 13.4% in the 6 mg of dexamethasone group (adjusted relative risk, 0.83 [99% CI, 0.54-1.29]). Conclusions and Relevance: Among patients with COVID-19 and severe hypoxemia, 12 mg/d of dexamethasone compared with 6 mg/d of dexamethasone did not result in statistically significantly more days alive without life support at 28 days. However, the trial may have been underpowered to identify a significant difference. Trial Registration: ClinicalTrials.gov Identifier: NCT04509973 and ctri.nic.in Identifier: CTRI/2020/10/028731.

Identification and characterization of a novel antimicrobial peptide compound produced by Bacillus megaterium strain isolated from oral microflora.

In recent years, the decreased efficacy of existing antibiotics toward management of emergent drug-resistant strains has necessitated the search for novel antibiotics from natural products. In this regard, Bacillus sp is well known for producing variety of secondary metabolites of potential use. Therefore, we performed an investigation to isolate and identify Bacillus sp from oral cavity for production of novel antimicrobial compounds. We extracted, purified, and identified a novel bioactive compound by B. megaterium (KC246043.1). The optimal production of compound was observed on de Man Rogosa and Sharpe broth by incubating at 37 °C, and pH 7.0 for 4 days. The bioactive compound was extracted by using n-butanol (2:1 v/v), purified on TLC plates with detection at Rf 7.8 cm; further characterized and identified as a cyclic ploypeptide sharing structural similarity with bacitracin. Minimum inhibitory concentration of bioactive compound was found to be 0.25, 0.5, 1.0, 3.125 and 6.25 µg/ml against Micrococcus luteus ATCC10240, Salmonella typhi ATCC19430, Escherichia coli ATCC35218. Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923 respectively, with no activity against Candida albicans ATCC10231. Our findings have revealed a novel cyclic peptide compound from B. megaterium with broad spectrum antimicrobial activity against both Gram positive and Gram negative bacteria.

Sub-MICs of Carum copticum and Thymus vulgaris influence virulence factors and biofilm formation in Candida spp.

BACKGROUND: Emergence of drug-resistant strains of Candida and inefficiency of conventional antifungal therapy has necessitated the search for alternative and new antifungal agents. Inhibition of virulence and biofilm are the potential drug targets. In this study, the oils of Carum copticum, Thymus vulgaris and their major active compound thymol as revealed by Gas chromatography and gas chromatography-mass spectrometry (GC-GC/MS) analysis were tested for their inhibitory activity against growth to determine sub-MIC values against 27 drug-resistant strains of Candida spp. METHODS: Brothmacrodilution method was used for determination of MIC of test oils against Candida strains. The spectrophotometric methods were used for detection and inhibition assays for virulence factors in Candida spp. Light and electron microscopy was performed to observe morphological effects of oils on biofilms. GC-GC/MS were used to evaluate the major active compounds of test oils. RESULTS: Virulence factors like proteinase and haemolysin were detected in 18 strains, both in solid and liquid media. A 70% of the test strains exhibited hydrophobicity and formed moderate to strong biofilms (OD280 0.5- > 1.0). Test oils exhibited MICs in the range of 45-360 µg.mL(-1) against the majority of test strains. All the oils at 0.25× and 0.5× MICs induced >70% reduction in the cell surface hydrophobicity, proteinase and haemolysin production. At 0.5× MIC, thymol and T. vulgaris were most inhibitory against biofilm formation. At sub-MICs electron microscopic studies revealed the deformity of complex structures of biofilms formed and cell membranes appeared to be the target site of these agents. CONCLUSIONS: Therefore, our findings have highlighted the concentration dependent activity of oils of C. copticum and T. vulgaris against virulence factors and biofilms in proteinase and haemolysin producing drug-resistant strains of Candida spp. The above activities of test oils are supposed to be mainly contributed due to their major active compound thymol. Further mechanism involving anti-proteinase, anti-haemolysin and anti-biofilm activities of these oils and compounds are to be explored for possible exploitation in combating Candida infections.

An in vitro and molecular informatics study to evaluate the antioxidative and ß-hydroxy-ß-methylglutaryl-CoA reductase inhibitory property of Ficus virens Ait.

The present study is initially intended to evaluate antioxidant and ß-hydroxy-ß-methylglutaryl-CoA reductase (HMGR) inhibitory property of Ficus virens Ait., first by in vitro analyses followed by a corroboratory molecular informatics study. Our results show that of all the sequentially extracted fraction of F. virens bark and leaves extract, F. virens bark methanol extract exhibits strong radical scavenging, antioxidant and oxidative DNA damage protective activity, which is well correlated with its total phenolic content. In addition, F. virens bark methanol extract, which is non-cytotoxic, significantly and non-covalently inhibit the HMGR activity (IC50 = 3.45 ± 0.45 µg/ml) in comparison with other extracts. The mechanistic aspect of this inhibition activity is authenticated by molecular docking study of bioactive compounds as revealed from gas chromatography-mass spectrometry data, with HMGR. The analysis for the first time indicates that quinic acid (ΔG: -8.11 kcal/mol) and paravastatin (ΔG: -8.22 kcal/mol) exhibit almost same binding energy, while other compounds also showed good binding energy, suggesting that quinic acid alone or in combination with other major bioactive compound is probably responsible for HMGR inhibitory property of the extract and plausibly can be used in in vivo system for the management, prevention, and alleviation of hypercholesterolemia as well as hypercholesterolemia-induced oxidative stress.

RP-HPLC Estimation of Flavonol Derivatives and Phenolic Acids in Capsicum annuum L. and their Correlation with In Vitro Anti-Inflammatory Activity.

BACKGROUND: Flavonol derivative and phenolic acids derived from the plants function as free radical scavengers, reducing agents, and quenchers for the formation of singlet oxygen. Flavonoids and phenolic constituents also play an important role in various human diseases and disorders primarily through modulation of inflammatory responses. OBJECTIVE: To estimate the Flavonol Derivatives (FD) and phenolic acids (PA) in Capsicum annuum (CA) and other important phytochemicals having an anti-inflammatory effect. METHODS: In the present study, FD and PA were estimated in CA and in vitro anti-inflammatory activity (pilot study) was determined and correlation was established. RESULTS: The results were found to be significant using RP-HPLC. FD and PA were found to be 0.0659±0.0058 and 0.0862±0.0.0134 mg/gram dry weight, respectively. For in vitro anti-inflammatory activity, the inhibition of albumin denaturation and antiproteinase activity was found to be maximum in Quercetin (QE) with 98.230±1.589% and 59.906±1.529%, respectively. Heat-induced hemolysis of erythrocytes was found to be maximum in salicylic acid (SA) (71.830±2.838%). Hypotonicity-induced hemolysis showed significant activity with QE (76.770±3.475%). Lipoxygenase and cyclooxygenase inhibition was found to be maximum in QE with 56.930±4.069% and 61.660±3.135%, respectively. CONCLUSION: A strong positive correlation of 0.9 was observed between the extract of CA and standard QE and SA against the anti-inflammatory activity. Therefore, the role of FD and PA has been postulated to be an active phytochemical of CA accountable for its anti-inflammatory activity. However further work is desirable to fully elucidate the phytochemicals responsible for their anti-inflammatory activity and to develop better herbal drug formulations.

Biosynthesized Silver Nanoparticle (AgNP) From Pandanus odorifer Leaf Extract Exhibits Anti-metastasis and Anti-biofilm Potentials.

Cancer and the associated secondary bacterial infections are leading cause of mortality, due to the paucity of effective drugs. Here, we have synthesized silver nanoparticles (AgNPs) from organic resource and confirmed their anti-cancer and anti-microbial potentials. Microwave irradiation method was employed to synthesize AgNPs using Pandanus odorifer leaf extract. Anti-cancer potential of AgNPs was evaluated by scratch assay on the monolayer of rat basophilic leukemia (RBL) cells, indicating that the synthesized AgNPs inhibit the migration of RBL cells. The synthesized AgNPs showed MIC value of 4-16 µg/mL against both Gram +ve and Gram -ve bacterial strains, exhibiting the anti-microbial potential. Biofilm inhibition was recorded at sub-MIC values against Gram +ve and Gram -ve bacterial strains. Violacein and alginate productions were reduced by 89.6 and 75.6%, respectively at 4 and 8 µg/mL of AgNPs, suggesting anti-quorum sensing activity. Exopolysaccharide production was decreased by 61-79 and 84% for Gram -ve and Gram +ve pathogens respectively. Flagellar driven swarming mobility was also reduced significantly. Furthermore, In vivo study confirmed their tolerability in mice, indicating their clinical perspective. Collective, we claim that the synthesized AgNPs have anti-metastasis as well as anti-microbial activities. Hence, this can be further tested for therapeutic options to treat cancer and secondary bacterial infections.

An Insight on the Pathogenesis and Treatment of Systemic Lupus Erythematosus.

BACKGROUND AND OBJECTIVE: Systemic lupus erythematosus (SLE) is a diverse autoimmune disorder, evoked in response to self-immune system that leads to immune complex depositions and organ damage. The exact mechanism of SLE pathogenesis is still unclear but certain genetic and environmental factors have been suggested that could influence its pathogenesis. DISCUSSION: The modulation in B- and T- cell responses and genetic variations could lead to abnormal lymphocyte functions and the production of antibodies against the indigenous proteins and the immune complex depositions. CONCLUSION: The present review highlights the various causatives of SLE, particularly the genetic alteration in B- and T-cell-related proteins. We have also delineated some of the available therapeutic strategies for the treatment of SLE.

Novel Strategies for Combating Pathogenic Biofilms Using Plant Products and Microbial Antibiosis.

Microorganisms prefer to live in three-dimensional self-organized communities (biofilms), and this behavior provides microbial pathogens inhabiting various sites in the human body or on medical devices with survival advantages. In fact, pathogens in the biofilm stage exhibit up to a thousandfold more tolerance to conventional antimicrobial agents, and thus, they are difficult to eradicate and biofilms generated during acute infections become persistent, chronic, and recurrent. Consequently, novel strategies are being sought to control biofilm associated infections. The developmental strategies used include improved drug delivery and the penetration of biofilm matrices, and in particular, natural products that interfere with virulence and cross talk between microbial cells are being investigated as potential anti-biofilm agents. This article provides an overview of existing and promising biofilm control strategies based on plant and microbial products. Control strategies like quorum sensing inhibition, microbial antibiosis, and the uses of phages and probiotics are reviewed along with current developments in high throughput screening and in our understanding of structure activity relationships related to the regulation of biofilms by small molecules.