Neutrophils display distinct post-translational modifications in response to varied pathological stimuli.

Neutrophils play a vital role in the innate immunity by perform effector functions through phagocytosis, degranulation, and forming extracellular traps. However, over-functioning of neutrophils has been associated with sterile inflammation such as Type 2 Diabetes, atherosclerosis, cancer and autoimmune disorders. Neutrophils exhibiting phenotypical and functional heterogeneity in both homeostatic and pathological conditions suggests distinct signaling pathways are activated in disease-specific stimuli and alter neutrophil functions. Hence, we examined mass spectrometry based post-translational modifications (PTM) of neutrophil proteins in response to pathologically significant stimuli, including high glucose, homocysteine and bacterial lipopolysaccharides representing diabetes-indicator, an activator of thrombosis and pathogen-associated molecule, respectively. Our data revealed that these aforesaid stimulators differentially deamidate, citrullinate, acetylate and methylate neutrophil proteins and align to distinct biological functions associated with degranulation, platelet activation, innate immune responses and metabolic alterations. The PTM patterns in response to high glucose showed an association with neutrophils extracellular traps (NETs) formation, homocysteine induced proteins PTM associated with signaling of systemic lupus erythematosus and lipopolysaccharides induced PTMs were involved in pathways related to cardiomyopathies. Our study provides novel insights into neutrophil PTM patterns and functions in response to varied pathological stimuli, which may serve as a resource to design therapeutic strategies for the management of neutrophil-centred diseases.

Osteoporosis management-current and future perspectives - A systemic review.

Introduction: Osteoporosis is a geriatric metabolic ailment distinguished by low bone mineral density (BMD) and strength with enhanced micro-architectural retrogression of the extracellular matrix, further increasing bone fragility risk. Osteoporotic fractures and associated complications become common in women and men after 55 and 65 years, respectively. The loss in BMD markedly enhances the risk of fracture, non-skeletal injury, and subsequent pain, adversely affecting the quality of life. Methods: Data summarised in this review were sourced and summarised, including contributions from 2008 to 2023, online from scientific search engines, based on scientific inclusion and exclusion criteria. Results: Biochemical serum markers such as BALP, collagen, osteocalcin, and cathepsin-K levels can reveal the osteoporotic status. DEXA scan techniques evaluate the whole body's BMD and bone mineral content (BMC), crucial in osteoporosis management. Anabolic and anti-osteoporotic agents are commonly used to enhance bone formation, minimize bone resorption, and regulate remodelling. The challenges and side effects of drug therapy can be overcome by combining the various drug moieties. Conclusion: The current review discusses the management protocol for osteoporosis, ranging from lifestyle modification, including physical exercise, pharmaceutical approaches, drug delivery applications, and advanced therapeutic possibilities of AI and machine learning techniques to reduce osteoporosis complications and fracture risk.

Protective effect of Pterospermum rubiginosum bark extract on bone mineral density and bone remodelling in estrogen deficient ovariectomized Sprague-Dawley (SD) rats.

Osteoporosis is a common metabolic old age disorder characterised by low bone mass content (BMC) and mineral density (BMD) with micro-architectural deterioration of the extracellular matrix, further increasing bone fragility risk. Several traditional remedies, including plant extracts and herbal formulations, are used worldwide by local healers to improve the overall bone health and metabolism as an excellent osteoregenerative agent. Pteropsermum rubiginosum is an underexplored medicinal plant used by tribal peoples of Western Ghats, India, to treat bone fractures and associated inflammation. The proposed study evaluates the elemental profiling and phytochemical characterisation of P. rubiginosum methanolic bark extract (PRME), along with detailed In vitro and In vivo biological investigation in MG-63 cells and Sprague-Dawley (SD) rats. AAS and ICP-MS analysis showed the presence of calcium, phosphorus, and magnesium and exceptional levels of strontium, chromium, and zinc in PRME. The NMR characterisation revealed the presence of vanillic acid, Ergost-4-ene-3-one and catechin. The molecular docking studies revealed the target pockets of isolated compounds and various marker proteins in the bone remodelling cycle. In vitro studies showed a significant hike in ALP and calcium content, along with upregulated mRNA expression of the ALP and COL1, which confirmed the osteoinductive activity of PRME in human osteoblast-like MG-63 cells. The in vivo evaluation in ovariectomised (OVX) rats showed remarkable recovery in ALP, collagen and osteocalcin protein after 3 months of PRME treatment. DEXA scanning reports in OVX rats supported the above in vitro and in vivo results, significantly enhancing the BMD and BMC. The results suggest that PRME can induce osteogenic activity and enhance bone formation with an excellent osteoprotective effect against bone loss in OVX animals due to estrogen deficiency. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-03942-7.

In silico, anti-inflammatory and acute toxicological evaluation of an indigenous medicinal plant Pterospermum rubiginosum using Sprague-Dawley rats.

BACKGROUND: Pterospermum rubiginosum has been traditionally used by the tribal inhabitants of Southern India for treating bone fractures and as a local anti-inflammatory agent; however, experimental evidence to support this traditional usage is lacking. The present study aimed to investigate the phytochemical characterization, in silico and in vitro anti-inflammatory evaluation, followed by in vivo toxicological screening of P. rubiginosum methanolic bark extract (PRME). RESULTS: The LCMS evaluation revealed the presence of 80 significant peaks; nearly 50 molecules were identified using the LCMS database. In silico analysis showed notable interactions with inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6). In vitro gene expression study supported the docking results with significant down-regulation of iNOS, IL-6, and IL-10. PRME was administered orally to the SD rats and was found to be non-toxic up to 1000 mg/kg body weight for 14 days. The antioxidant enzymes catalase and sodium dismutase exhibited an increased value in PRME-administered groups, possibly due to the diverse phytochemical combinations in bark extract. CONCLUSIONS: PRME administration significantly downregulated the gene expression of inflammatory markers, such as iNOS, IL-6, and IL-10. The molecular docking analysis of iNOS and IL-6 supports the in vitro study. In vivo toxicological study of PRME in SD rats was found to be non-toxic up to a concentration of 1000 mg/kg body weight for 14 days.

Targeting the Role of PRME in Regulating Bone Remodelling During Postmenopausal Osteoporosis.

Kariavattom Campus Postmenopausal osteoporosis (PMO) is an old age disorder associated with estrogen deficiency, which reduces bone mass and makes bones more prone to fracture. The present study was proposed to evaluate the invivo osteogenic efficiency of Pterospermum rubiginosum methanolic bark extract (PRME) in the PMO model. Molecular docking studies on transcription factor NFATC1 showed excellent interactions with phytochemical ligands with the lowest binding energies. Female Sprague Dawley (SD) rats (n=24) were divided into four groups, (n=6 each) sham control (Group I) and osteoporotic control (Group II) groups treated with saline, PRME (50 mg/kg/day) and alendronate (10 mg/kg/day) treated with Group III and Group IV (n=6) respectively. The serum tartrate-resistant acid phosphatase 5b and cathepsin-K also exhibited a significant rise after PRME treatment 12.33±2.30 mU/ml and 427.68±46.97 pg/ml, respectively. DEXA results exhibited a remarkable increase in total bone mineral content and density values in PRME-treated animals (0.175±0.002 g/cm2) and (7.95±0.23 g) when compared to osteoporotic control (0.163±0.004 g/cm2) and (6.83±0.34 g). Long-term toxicity study revealed that PRME is non-toxic, up to 100 mg/kg bodyweight for 6 months. Our findings suggest PRME protects osteoporotic SD rats from PMO damage resulting from estrogen deficiency by regulating bone remodelling markers and upregulating BMD indices.

Epigenetic regulation of the nuclear genome associated with mitochondrial dysfunction in Leber's hereditary optic neuropathy (LHON).

Leber's hereditary optic neuropathy (LHON) is a mitochondrial hereditary disease in which visual loss affects complex 1 activity of the electron transport chain of mitochondria. It first manifests as painless dulling or blurry in one or even both eyes, and as it develops, sharpness and color perception are lost. In addition to primary mitochondrial DNA (mtDNA) mutations, there are also other environmental and epigenetic factors involved in the pathogenesis of LHON. One of the most common locations for deadly pathogenic mutations in humans is the human complex I accessory NDUFS4 subunit gene. The iron-sulfur clusters of the electron input domain were distorted in the absence of NDUFS4, which reduced complex I function and elevated the production of reactive oxygen species. Therefore, here, we studied the epigenetic alterations of NDUFS4 by focusing on histone activation and repressive markers. We isolated peripheral blood mononuclear cells (PBMCs) from LHON patients and healthy individuals and examined epigenetic modifications in ND4 mutant cells and control cells. Chromatin immunoprecipitation-qRT PCR (ChIP-qRT PCR) assays were performed to investigate the modifications of histones. In comparison to their controls, both LHON patients and ND4 mutant cells exhibited a significant enrichment in activation and repressive markers. This finding indicates that these modifications might mitigate the impact of LHON mutations on complex 1 and aid in elucidating the mechanism underlying the progression of LHON disease.

Retinal Changes in Parkinson's Disease: A Non-invasive Biomarker for Early Diagnosis.

Parkinson's disease (PD) is caused due to degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc) which leads to the depletion of dopamine in the body. The lack of dopamine is mainly due to aggregation of misfolded α-synuclein which causes motor impairment in PD. Dopamine is also required for normal retinal function and the light-dark vision cycle. Misfolded α-synuclein present in inner retinal layers causes vision-associated problems in PD patients. Hence, individuals with PD also experience structural and functional changes in the retina. Mutation in LRRK2, PARK2, PARK7, PINK1, or SNCA genes and mitochondria dysfunction also play a role in the pathophysiology of PD. In this review, we discussed the different etiologies which lead to PD and future prospects of employing non-invasive techniques and retinal changes to diagnose the onset of PD earlier.

Volatile organic compound sensing in breath using conducting polymer coated chemi-resistive filter paper sensors.

In this work, a disposable sensor array was designed based on the chemi-resistive behavior of the conducting polymers to detect three volatile organic compounds (VOCs), i.e., acetone, ethanol, and methanol in air and breath. Four disposable resistive sensors were designed by coating polypyrrole and polyaniline (in their doped and de-doped forms) on filter paper substrates and tested against VOCs in air. Change in conductivity of the polymer resulting from exposure to various VOC concentration was measured as percentage resistance change using a standard multimeter. The lowest concentration detected for acetone, ethanol, and methanol vapors was 400 ppb, 150 ppb, and 300 ppb, respectively within 2 min. These VOC-responsive sensors, housed in an indigenous inert chamber, showed good stability, repeatability, and reversibility while sensing, thus making it suitable for environmental pollutant detection at room temperature. Furthermore, the non-specific nature of these easy to fabricate sensors towards all VOCs is considered favorable and upon classifying with principal component analysis (PCA), the gases were qualitatively distinguished in separate clusters. These developed sensors were also tested and analyzed using VOC spiked real breath samples as proof of concept.

Advantages of mesenchymal stem cell over the other stem cells.

A stem cell is a particular group of cells that has the extraordinary potential to convert within the body into particular cell types. They are used to regenerate tissues and cells in the body that have been damaged or destroyed by the disease. Stem cells come in three different varieties: adult stem cells, embryonic stem cells and induced pluripotent stem cells (iPSCs). Embryonic stem cells have a high chance of immune rejection and also have ethical dilemmas and iPSCs have genetic instability. Adult stem cells are difficult to analyze and extract for research since they are frequently insufficient in native tissues. However, mesenchymal stem cells (MSC) one of the categories of adult stem cells are stromal cells with a variety of potentials that can differentiate into a wide range of cell types. MSCs can be transplanted into a variety of people without worrying about rejection because they have demonstrated the ability to prevent an adverse reaction from the immune system. These transplants have powerful anti-inflammatory and immunosuppressive effects and greatly enhance the body's inherent healing capacity. While MSCs do not offer treatment for illnesses, the idea behind them is to enable the body to recover sufficiently for a protracted reduction in symptoms. In many cases, this is sufficient to significantly enhance the patient's well-being. Inspite of several advantages some potential long-term concerns connected to MSC therapy are maldifferentiation, immunosuppression and cancerous tumor growth. In this review, we will compare the mesenchymal stem cells with other stem cells with respect to the source of origin, their properties and therapeutic applications, and discuss the MSC's disadvantages.

Neutrophil (dys)function due to altered immuno-metabolic axis in type 2 diabetes: implications in combating infections.

Metabolic and inflammatory pathways are highly interdependent, and both systems are dysregulated in Type 2 diabetes (T2D). T2D is associated with pre-activated inflammatory signaling networks, aberrant cytokine production and increased acute phase reactants which leads to a pro-inflammatory 'feed forward loop'. Nutrient 'excess' conditions in T2D with hyperglycemia, elevated lipids and branched-chain amino acids significantly alter the functions of immune cells including neutrophils. Neutrophils are metabolically active cells and utilizes energy from glycolysis, stored glycogen and ß-oxidation while depending on the pentose phosphate pathway for NADPH for performing effector functions such as chemotaxis, phagocytosis and forming extracellular traps. Metabolic changes in T2D result in constitutive activation and impeded acquisition of effector or regulatory activities of neutrophils and render T2D subjects for recurrent infections. Increased flux through the polyol and hexosamine pathways, elevated production of advanced glycation end products (AGEs), and activation of protein kinase C isoforms lead to (a) an enhancement in superoxide generation; (b) the stimulation of inflammatory pathways and subsequently to (c) abnormal host responses. Neutrophil dysfunction diminishes the effectiveness of wound healing, successful tissue regeneration and immune surveillance against offending pathogens. Hence, Metabolic reprogramming in neutrophils determines frequency, severity and duration of infections in T2D. The present review discusses the influence of the altered immuno-metabolic axis on neutrophil dysfunction along with challenges and therapeutic opportunities for clinical management of T2D-associated infections.

An integrated approach to the structural characterization, long-term toxicological and anti-inflammatory evaluation of Pterospermum rubiginosum bark extract.

ETHNOPHARMACOLOGICAL RELEVANCE OF STUDY: Pterospermum rubiginosum is an evergreen plant in Western Ghats, India, used by traditional tribal healers due to its excellent biological potential for treating inflammation and pain relief procedures. The bark extract is also consumed to relieve the inflammatory changes at the bone fractured site. The traditional medicinal plant in India have to be characterized for its diverse phytochemical moieties, its interactive multiple target sites, and to reveal the hidden molecular mechanism behind the biological potency. AIM OF THE STUDY: The study focussed on plant material characterization, computational analysis (prediction study), toxicological screening (In vivo), and anti-inflammatory evaluation of P. rubiginosum methanolic bark extracts (PRME) in LPS-induced RAW 264.7 cells. MATERIALS AND METHODS: The pure compound isolation of PRME and their biological interactions were used to predict the bioactive components, molecular targets, and molecular pathways of PRME in inhibiting inflammatory mediators. The anti-inflammatory effects of PRME extract were evaluated in the lipopolysaccharide (LPS)-induced RAW264.7 macrophage cell model. The toxicity evaluation of PRME was performed in healthy 30 Sprague-Dawley experimental rats, were randomly divided into five groups for toxicological evaluation for 90 days. The tissue levels of oxidative stress and organ toxicity markers were measured using the ELISA method. Nuclear magnetic resonance spectroscopy (NMR) was performed to characterize the bioactive molecules. RESULTS: Structural characterization revealed the presence of vanillic acid, 4-O-methyl gallic acid, E-resveratrol, gallocatechin, 4'-O-methyl gallocatechin, and catechin. Molecular docking of NF-kB exhibited significant interactions with vanillic acid and 4-O-methyl gallic acid with binding energy -351.159 Kcal/Mol and -326.5505 Kcal/Mol, respectively. The PRME-treated animals showed an increase in total GPx and antioxidant levels (SOD and catalase). Histopathological examination revealed no variation in the liver, renal and splenic tissue's cellular pattern. PRME inhibited the pro-inflammatory parameters (IL-1ß, IL-6, and TNF-α) in LPS-induced RAW 264.7 cells. The protein level of TNF-α and NF-kB protein expression study brought out a notable reduction and exhibited a good correlation with the gene expression study. CONCLUSION: The current study establishes the therapeutic potential of PRME as an effective inhibitory agent against LPS-activated RAW 264.7 cells induced inflammatory mediators. Long-term toxicity evaluation on SD rats confirmed the non-toxic nature of PRME up to 250mg/body weight for 3 months.

Oxidative stress and mitochondrial transfer: A new dimension towards ocular diseases.

Ocular cells like, retinal pigment epithelium (RPE) is a highly specialized pigmented monolayer of post-mitotic cells, which is located in the posterior segment of the eye between neuro sensory retina and vascular choroid. It functions as a selective barrier and nourishes retinal visual cells. As a result of high-level oxygen consumption of retinal cells, RPE cells are vulnerable to chronic oxidative stress and an increased level of reactive oxygen species (ROS) generated from mitochondria. These oxidative stress and ROS generation in retinal cells lead to RPE degeneration. Various sources including mtDNA damage could be an important factor of oxidative stress in RPE. Gene therapy and mitochondrial transfer studies are emerging fields in ocular disease research. For retinal degenerative diseases stem cell-based transplantation methods are developed from basic research to preclinical and clinical trials. Translational research contributions of gene and cell therapy would be a new strategy to prevent, treat and cure various ocular diseases. This review focuses on the effect of oxidative stress in ocular cell degeneration and recent translational researches on retinal degenerative diseases to cure blindness.

Quantitative phosphoproteomics reveals diverse stimuli activate distinct signaling pathways during neutrophil activation.

Neutrophils display functional heterogeneity upon responding diversely to physiological and pathological stimulations. During type 2 diabetes (T2D), hyperglycemia constitutively activates neutrophils, leading to reduced response to infections and on the other hand, elevated metabolic intermediates such as homocysteine induce bidirectional activation of platelets and neutrophils leading to thrombosis. Hence, in the context of T2D-associated complications, we examined the influence of high glucose, homocysteine, and LPS representing effector molecules of hyperglycemia, thrombosis, and infection, respectively, on human neutrophil activation to identify distinct signaling pathways by quantitative phosphoproteomics approach. High glucose activated C-Jun-N-Terminal Kinase, NTRK1, SYK, and PRKACA kinases associated with Rho GTPase signaling and phagocytosis, whereas LPS induced AKT1, SRPK2, CSNK2A1, and TTN kinases involved in cytokine signaling and inflammatory response. Homocysteine treatment led to activatation of  LRRK2, FGR, MAPK3, and PRKCD kinases which are associated with neutrophil degranulation and cytoskeletal remodeling. Diverse inducers differentially modulated phosphorylation of proteins associated with neutrophil functions such as oxidative burst, degranulation, extracellular traps, and phagocytosis. Further validation of phosphoproteomics data on selected kinases revealed neutrophils pre-cultured under high glucose showed impeded response to LPS to phosphorylate p-ERK1/2Thr202/Tyr204, p-AKTSer473, and C-Jun-N-Terminal KinaseSer63 kinases. Our study provides novel phosphoproteome signatures that may be explored to understand neutrophil biology in T2D-associated complications.

Clinico-Microbiological Profile and Culture Sensitivity Pattern of Micro-Organisms Isolated from Diabetic Foot Ulcers: Study from a Tertiary Care Centre.

Worldwide, diabetic foot lesions are a major medical, social and economic problem and are the leading cause of hospitalization for patients with diabetes. The organisms causing the ulcers vary from different geographical regions and initiation of empiric antibiotics depends on the prevalence of the local pathogens and their sensitivity pattern, With this background the present study was carried out to evaluate the bacterial diversity and their culture sensitivity patterns in diabetic foot ulcers. MATERIAL: Medical records of 65 cases of diabetes mellitus with diabetic foot ulcer admitted to hospital during the period from January 2019 to December 2020 were retrieved from the Medical Records Department. Demographic, clinical profile and microbiological profile with antibiotic sensitivity pattern were analyzed. OBSERVATION: Out of 65 cases (n=65), 54 (83.07%) were male and 11 (16.92%) were female. Age range of the patients was from 39 years to 80 years with mean age of 59=/-9.65years. The mean duration of diabetes was 9.4=/-5.7 years and 52.4% had diabetes for more than 10 years. Hypertension was present in 84.5% of the cases. Nearly 62.5% had lesions for 3 months before presenting to the hospital. Peripheral neuropathy was present in all the cases. More than 60% cases were surgically treated with debridement. Osteomyelitis was present in 44.5% cases. Out of 65 cases, 64 were culture positive. Pseudomonas aeruginosa was the leading pathogen in 23.3% cases (n=15), Staphylococcus aureus, E.coli, Acinetobacter baumannii and Klebsiella pneumoniae were isolated in 15.38% cases each followed by Burkholderia cepacia which constituted 10% of all cases. Multiple organisms were isolated in 11 cases (16.92%). CONCLUSION: Burkholderia cepacia, which was earlier an uncommon infection in Diabetic foot ulcer, was found in significant (10%) number of cases. This may be due to improper waste management and change in environmental conditions.

Artesunate Resistance - An Emerging Threat.

Drug resistant malaria represents a challenging health problem in developing countries like India. The failure of drug artemisinin, which is the cornerstone of malaria therapy will rapidly compromise the treatment and prognosis of malaria. Resistance should be suspected if inspite of full treatment with Artesunate Combination Therapy and with no history of vomiting or diarrhoea, there is no clinical or parasitological response in the patient after 72 hours. The emergence of partial artemisinin resistant parasites were previously reported from West Bengal in the form of resistance to drugs. Presence of mutations in molecular markers was reported from different parts of India (Uttar Pradesh,Andhra Pradesh,Odisha and Jharkhand). MATERIAL: We report four cases of complicated malaria in Eastern India between January 2020 and July 2021, with apparent treatment failure with artemisinin drugs. Case1 A 45 old male known diabetic and hypertensive presenting with fever with loose stools since 5 days and seizures since 1 day. Case 2 A 59 year old male patient, known diabetic admitted with fever,black stools and decreased urination for 10 days. Case 3 A 35 year old male patient admitted with fever, headache, vomiting and hematuria for 5 days. Case 4 A 25 year old pregnant female admitted with complaints of bleeding per vaginum since 10 days with fever and vomiting for 6 days. In all cases malaria was confirmed with rapid card test and peripheral smears showed ring forms of plasmodium falciparum.Parasite levels were estimated to be between 30% to 45% in all cases.The patients were treated with injectable artesunate and once they tolerated oral medication they were started on oral artesunate combination therapy. OBSERVATION: After 4 days repeat peripheral smears showed persistence of parasites. Organ dysfunction did not subside. Hence Injectable Quinine and clindamycin was started in all cases. On day 7 all obtained microscopic parasite clearance. Cases 2 and 4 attained complete recovery,but the other two cases developed multiorgan dysfunction followed by septic shock and succumbed on 11th and 14th day of admission respectively. We could not confirm artemisinin resistance in any of these cases due to lack of availability of gene testing in our area. CONCLUSION: This report emphasizes the need for increased surveillance to identify artemisinin resistance in India. It will aid the treating physician for more selective use of drug-combinations which are less likely to foster resistance.

Mesenchymal stem cells (MSCs) in Leber's hereditary optic neuropathy (LHON): a potential therapeutic approach for future.

BACKGROUND: Optic neuropathy has become a new typical syndromic multi-system disease that leads to optic atrophy. This review discusses potential treatments and advances of Leber's hereditary optic neuropathy (LHON), a sporadic genetic disorder. LHON is caused due to slight mutations in mitochondria leading to mitochondrial dysfunction, causing vision loss. There are no current significant treatments that have been proven to work for LHON. METHODS: However, extensive review was carried out on capable studies that have shown potential treatment sensory systems and are being evaluated currently. Some of these studies are in clinical trials, whereas other ones are still being planned. Here, we focus more on treatment based on mesenchymal stem cells-mediated mitochondrial transfer via various techniques. We discuss different mitochondrial transfer modes and possible ways to understand the mitochondria transfer technique's phenotypic characteristics. CONCLUSION: It is clearly understood that transfer of healthy mitochondria from MSC to target cell would regulate the range of reactive oxygen species and ATP'S, which are majorly responsible for mutation upon irregulating. Therefore, mitochondrial transfer is suggested and discussed in this review with various aspects. The graphical abstract represents different means of mitochondrial transport like (a) Tunnelling nanotubules, (b) Extracellular vesicles, (c) Cell fusion and (d) Gap junctions. In (a) Tunnelling nanotubules, the signalling pathways TNF- α/TNF αip2 and NFkB/TNF αep2 are responsible for forming tunnels. Also, Miro protein acts as cargo for the transport of mitochondria with myosin's help in the presence of RhoGTPases [35]. In (b) Extracellular vesicles, the RhoA ARF6 contributes to Actin/Cytoskeletal rearrangement leading to the shedding of microvesicles. Coming to (c) Cell fusion when there is a high amount of ATP, the cells tend to fuse when in close proximity leading to the transfer of mitochondria via EFF-1/HAP2 [48]. In (d) Gap Junctions, Connexin43 is responsible for the intracellular channel in the presence of more ATP [86].

Modulation of neutrophil (dys)function by Ayurvedic herbs and its potential influence on SARS-CoV-2 infection.

For centuries, traditional medicines of Ayurveda have been in use to manage infectious and non-infectious diseases. The key embodiment of traditional medicines is the holistic system of approach in the management of human diseases. SARS-CoV-2 (COVID-19) infection is an ongoing pandemic, which has emerged as the major health threat worldwide and is causing significant stress, morbidity and mortality. Studies from the individuals with SARS-CoV-2 infection have shown significant immune dysregulation and cytokine overproduction. Neutrophilia and neutrophil to lymphocyte ratio has been correlated to poor outcome due to the disease. Neutrophils, component of innate immune system, upon stimulation expel DNA along with histones and granular proteins to form extracellular traps (NETs). Although, these DNA lattices possess beneficial activity in trapping and eliminating pathogens, NETs may also cause adverse effects by inducing immunothrombosis and tissue damage in diseases including Type 2 Diabetes and atherosclerosis. Tissues of SARS-CoV-2 infected subjects showed microthrombi with neutrophil-platelet infiltration and serum showed elevated NETs components, suggesting large involvement and uncontrolled activation of neutrophils leading to pathogenesis and associated organ damage. Hence, traditional Ayurvedic herbs exhibiting anti-inflammatory and antioxidant properties may act in a manner that might prove beneficial in targeting over-functioning of neutrophils and there by promoting normal immune homeostasis. In the present manuscript, we have reviewed and discussed pathological importance of NETs formation in SARS-CoV-2 infections and discuss how various Ayurvedic herbs can be explored to modulate neutrophil function and inhibit NETs formation in the context of a) anti-microbial activity to enhance neutrophil function, b) immunomodulatory effects to maintain neutrophil mediated immune homeostasis and c) to inhibit NETs mediated thrombosis.

Glucose induces metabolic reprogramming in neutrophils during type 2 diabetes to form constitutive extracellular traps and decreased responsiveness to lipopolysaccharides.

Recurrent infections are one of the common morbidities in Type 2 Diabetes (T2D) subjects. Bidirectional activation of innate immune cells such as neutrophils and glucose metabolism in T2D conditions leads to a pro-inflammatory milieu and reduced neutrophil function, which can be a potential cause for recurrent infections. In pathological conditions of sterile inflammation associated T2D, neutrophils form constitutive extracellular traps (NETs) due to hyperglycemia and respond poorly to infections. The present study was aimed at understanding the cellular and metabolic consequences, and NETs formation in T2D. We show that glucose induces NADPH oxidase derived reactive oxygen species and further citrullinates the histones to form weaker NETs leading to reduced response to lipopolysaccharide (LPS). Untargeted metabolomics analysis in neutrophils cultured under high glucose and from T2D subjects revealed enrichment of polyol pathway intermediates (1-anhydrosorbitol) and reduced glutathione metabolism products (cysteinylglycine). NADPH is an absolute requirement for three independent pathways of formation of 1-anhydrosorbitol via aldose reductase under excess glucose, induction of glutathione synthesis and glucose induced NETs formation. During T2D and in presence of high glucose, there is a competition for NADPH between these processive reactions, which leads to its insufficiency to produce NETs in response to LPS. Interestingly, supplementation of NADPH and pharmacological inhibitor of aldose reductase, ranirestat, restored NETs formation in presence of LPS. Our study provides novel insights on the metabolic reprogramming of neutrophils, which may lead to susceptibility of T2D subjects to infections.

Plant-pathogen interactions: MicroRNA-mediated trans-kingdom gene regulation in fungi and their host plants.

MicroRNAs (miRNAs) have been prevalently studied in plants, animals, and viruses. However, recent studies show evidences of miRNA-like RNAs (milRNAs) in fungi as well. It is known that after successful infection, pathogens hijack the host machinery and use it for their own growth and multiplication. Alternatively, resistant plants can overcome the pathogen attack by a variety of mechanisms. Based on this prior knowledge, we computationally predicted milRNAs from 13 fungi, and identified their targets in transcriptomes of the respective fungi as well as their host plants. The expressions of the milRNAs and targets were confirmed using qRT-PCR. We found that plant miRNAs targeted fungal virulence genes, while fungal milRNAs targeted plant resistance genes; corroborating miRNA-mediated trans-kingdom gene regulation and the roles of miRNAs in plant-pathogen interactions. Transgenic plants with miRNAs targeting fungal virulence genes, or anti-sense of fungal milRNAs, would be expected to be highly resistant to the fungal pathogens.

Role of Jasmonate in Modulation of Mycorrhizae-Induced Resistance Against Fungal Pathogens.

Symbiotic association of plants with arbuscular mycorrhizal (AM) fungi brings about changes in levels of the phytohormone jasmonate (JA) in root and shoot tissues of a plant. The enhanced JA levels not only play a role in controlling the extent of AM colonization but are also involved in the expression of mycorrhizal-induced resistance (MIR) against pathogens. We describe a method used to study the levels of a volatile jasmonate derivative, methyl jasmonate (MeJA), in tomato plants colonized by AM fungi and in response to subsequent attack by the foliar pathogen Alternaria alternata.