Department of Biotechnology

About: Department of Biotechnology is a government organization based out in New Delhi, India. It is known for research contribution in the topics: Population & Silver nanoparticle. The organization has 4800 authors who have published 5033 publications receiving 82022 citations.

Co-supplementation of isomalto-oligosaccharides potentiates metabolic health benefits of polyphenol-rich cranberry extract in high fat diet-fed mice via enhanced gut butyrate production

Abstract: Cranberries are a rich source of polyphenolic antioxidants. Purified sugars or artificial sweeteners are being added to cranberry-based food products to mask tartness. Refined sugar and artificial sweeteners intake modulate gut microbiota and result in metabolic complications. We evaluated effects of isomalto-oligosaccharides (IMOs; sweet tasting non-digestible oligosaccharides) with cranberry extract (CRX) on high fat diet (HFD)-induced metabolic alterations in mice. Male Swiss albino mice were fed normal chow or HFD (58% fat kcal), and were administered either CRX (200 mg/kg) alone or in combination with IMOs (1 g/kg). Cecal short-chain fatty acids, abundances of selected (1) butyrate producing, (2) metabolically beneficial, and (3) selective lipopolysaccharides producing gram negative gut bacteria were studied. Further, gut-related histological, biochemical, genomic changes along with circulating pro-/anti-inflammatory markers and systemic obesity-associated metabolic changes were studied. Co-supplementation of CRX and IMOs significantly improved cecal SCFAs, especially butyrate levels, selected butyrate-producing bacteria (clostridial cluster XIVa bacteria) and butyrate kinase expression in HFD-fed mice. The combination also significantly improved gut beneficial bacterial abundance, gut histology and related changes (colon mucin production, gut permeability) as compared to individual agents. It also prevented HFD-induced systemic and tissue inflammation, glucose intolerance and systemic obesity-associated metabolic changes in adipose tissue and liver. The combination of CRX and IMOs appeared more effective in the prevention of HFD-induced gut derangements. Combination of CRX and IMOs could be advantageous for normalization of metabolic alterations seen in diet-induced obesity via beneficial modulation of gastrointestinal health.

Mitochondria-mediated hormetic response in life span extension of calorie-restricted Saccharomyces cerevisiae.

Abstract: Calorie restriction (CR) is the only proven regimen, which confers lifespan extension benefits across the various phyla right from unicellular organisms like yeast to primates. In a bid to elucidate the mechanism of calorie-restriction-mediated life span extension, the role of mitochondria in the process was investigated. In this study, we found that the mitochondrial content in CR cells remains unaltered as compared to cells grown on nonrestricted media. However, mitochondria isolated from CR cells showed increased respiration and elevated reactive oxygen species levels without augmenting adenosine triphosphate (ATP) generation. The antioxidant defense system was amplified in CR mitochondria, and in CR cells a cross protection to hydrogen-peroxide-induced stress was also observed. Moreover, we also documented that a functional electron transport chain was vital for the life span extension benefits of calorie restriction. Altogether, our results indicate that calorie restriction elicits mitohormetic effect, which ultimately leads to longevity benefit.

Difference in keratinase activity of dermatophytes at different environmental conditions is an attribute of adaptation to parasitism.

Abstract: Dermatophytes are a group of morphologically and physiologically related moulds, which cause well-defined infection called dermatophytosis. The enzymatic ability of fungi to decompose keratin has long been interpreted as a key innovation in the evolution of animal dermatology. In the present study, keratinase activity profile among Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Microsporum gypseum isolated on keratin substrates such as human hair, human nail and chicken feather at variable environmental conditions of temperature, pH and metal ions was elucidated. All the above-mentioned fungal strains were isolated from soil using To-KA-Va baiting technique and keratinolytic activity was measured spectrophotometrically. In the temperature range of 30-40 °C and slightly alkaline pH (7.0-8.0), Trichophyton produced the highest activity of keratinase. It can be presumed that high enzyme production of Trichophyton species at normal body temperature range and pH could be an attribute for obligate anthropization in some dermatophytes.

Exosome mediated miR-155 delivery confers cisplatin chemoresistance in oral cancer cells via epithelial-mesenchymal transition.

Abstract: Cisplatin is used as chemotherapeutic drug for oral squamous cell carcinoma (OSCC). However, OSCC cells develop resistance following long-term cisplatin exposure. Resistance against cisplatin chemo-therapy is accredited to the process of epithelial-to-mesenchymal transition, which in-turn has been linked to tumor-recurrence. miRNA deregulation, a common event in cancer, plays contributory role in chemo-resistance. Exosomes acts as the natural cargo for miRNA and facilitates inter-cell communication in the tumor micro-environment. Hence, exosomal-mediated miRNA transference may play essential role in drug resistance and serve as a target for cancer-therapy. miR-155 upregulation in OSCC has been described, however, its relevance in the observed chemo-resistance is unclear and also, if exosomes have any role in miR-155 regulation remain elusive. In the present study, we document for the first time the critical role of exosomes in mediating increments in miR-155 expression in OSCC cells that have acquired cisplatin resistance (cisRes cells). Importantly, exosomal transfer from cisRes to the cisplatin sensitive (cisSens) cells was found to confer significant miR-155 induction in the recipient cisSens cells. Restoration of miR-155 expression in cisSens cells following miR-155 mimics treatment led to epithelial to mesenchymal transition, enhancements in their migratory potential as well as acquisition of resistant phenotype. Notably, similar augmentations in the migratory and chemo-resistant traits were seen upon delivery of exosomes from cisRes to the recipient cisSens cells. Overall, our findings establish the significance of exosomal-mediated miR-155 shuttling in the cisplatin-chemoresistance, commonly observed in OSCC cells, thereby providing rationale for targeting miR-155 signalling for oral cancer therapy.