6-Gingerdione Reduces Apoptotic Conditions in HepG2 Cells and Inhibits Inflammatory Cytokine Gene Expression in Alcoholic Liver Injured Zebrafish Larvae

Antioxidant natural products and their analogs especially phenolic compounds, exhibit diverse biological properties, including anti-inflammatory, antioxidant, and anticancer activities. Ginger which is widely used worldwide for various beneficial effects also contains several phenolic antioxidants, and 6-gingerol is one of the natural products studied extensively. However, the molecular mechanism of synthetically synthesized 6-gingerdione (compound 1) from 6-gingerol was not known. In this study, compound 1 and methylated 6-gingerdione (compound 2) were obtained semi synthetically from 6-gingerol. Compound 1 and 2 are subjected to SwissADME prediction. Then the protective effect of compound 1 was analyzed in 2 % EtOH induced HepG2 cells and zebrafish larvae. Hydroxyl and nitric oxide scavenging assays reveal that compound 1 showed more antioxidant activity than compound 2 at 50 μM. Moreover, compound 1 exhibited good anti-inflammatory activity via lipoxygenase inhibition and proteinase inhibition. Apoptosis and oxidative stress in HepG2 cells were induced by 2 % EtOH and treated with compound 1. Compound 1 significantly inhibited the EtOH induced nitric oxide production, apoptosis, and ROS generation in HepG2 cells. Encouraged by the in-vitro antioxidant and anti-inflammatory activities, compound 1 was then investigated for its protective effect in 2 % EtOH induced ALD zebrafish larva. Compound 1 protected the zebrafish larvae from liver injury by suppressing inflammatory (COX-2, TNF-α, and IL-1β) and lipogenic genes (C/EBP-α, SREBP1, and IL-1β) while upregulating the antioxidant gene. Our findings indicate that compound 1 synthesized from 6-gingerol ameliorated liver injury that likely, contributes to its potential antioxidant and anti-inflammatory properties.

Long non‐coding RNA, a supreme post‐transcriptional immune regulator of bacterial or virus‐driven immune evolution in teleost

The global aquaculture boom, fuelled by a reduction in wild population and detection of novel viruses, has created a demanding market, hence, there is a pressing need to investigate the immune system of fish, further. As the most diverse community of vertebrates and a central contributor to the progressing global aquaculture market, teleost continues to draw vast scientific interest. Recent breakthroughs in multi‐omics technologies have provided a platform to understand the role of long non‐coding RNA (lncRNA) in the host immune system during infection. Emerging evidence shows that teleost lncRNA might have a regulatory role in immune responses, mostly through lncRNA–microRNA (miRNA) sponging. Teleost lncRNA shares a functionally active short sequence complement to target the miRNA which is conserved among the several fish species. Recent report suggests that rhabdovirus exploits a lncRNA in teleost and, to dodge the host immune mechanism and negatively regulate the immune system. This observation reveals the essentiality of lncRNA in pathogen‐driven immunity in teleost. Reports available on the function of teleost lncRNA are still in early stages and experimental verifications are a limiting factor. Unravelling the lncRNA‐mediated immune regulation in fishes could be used against the invading pathogens to strengthen the aquaculture production. This review elaborates on the experimentally identified and functionally characterized lncRNA and its regulatory role in the teleost immune response during infection and pathogen‐driven host immune evolution, which could eventually lead to achieving high standards in aquaculture productivity.

Exposure to environmental pollutant bisphenol A causes oxidative damage and lipid accumulation in Zebrafish larvae: Protective role of WL15 peptide derived from cysteine and glycine-rich protein 2

Humans are exposed to obesity causing Bisphenol A in various ways, especially through diet and food containers. Bioactive peptides are already reported to have antioxidant, antidiabetic, and antiobesity properties, which can mimic the role of mediators involved in obesity prevention. The protective effect of a short molecule or peptide, WL15 from cysteine and glycine-rich protein 2 of a teleost of aquatic resource on Bisphenol A (BPA)-induced lipid accumulation in zebrafish larvae was investigated. BPA exposure disrupted the antioxidant enzymes, apoptosis, and nitric oxide and led to changes in biochemical markers including alkaline phosphatase, lactate dehydrogenase, lipid peroxidation, glutathione S-transferases, glutathione peroxidase, and reduced glutathione. However, WL15 inhibited the overproduction of oxidative stress, which correlates with its lipid-lowering potential. BPA-induced lipid accumulation in zebrafish showed an increase in triglyceride, cholesterol, and glucose level; simultaneously, WL15 treatment significantly reduced such accumulation in zebrafish. Evidenced by Oil red O staining and Nile red assay, WL15 inhibited lipid accumulation. At the same time, WL15 at 50 µM increases 2-(N-[7-nitrobenz-2-oxa-1,3-diazol-4-yl]amino)-2-deoxy-d-glucose (2NBDG) glucose uptake in zebrafish. In addition, gene expression studies in zebrafish larvae demonstrated that the WL15 peptide could play a crucial role in preventing lipid accumulation by downregulating the expression of lipogenesis-specific genes. These results revealed an interesting and novel property of WL15, suggesting its potential application in preventing lipid accumulation through the hypolipidemic and antioxidant properties.

Copper sulfate induced toxicological impact on in-vivo zebrafish larval model protected due to acacetin via anti-inflammatory and glutathione redox mechanism

Copper sulfate (CuSO₄) as industrial effluent is intentionally or unintentionally released into water bodies and accumulates in the fish. Because of its numerous applications, CuSO₄ can be hazardous to non-target creatures, producing direct alterations in fish habitats. Acacetin is a flavonoid present in all vascular plants that are extensively dispersed in plant pigments and responsible for many natural hues. However, the impact of acacetin on mitigating the toxic effect of CuSO₄ in the in-vivo conditions is not known. The toxicity of acacetin was determined by measuring the survival, deformities and heart rate after treatment with various concentrations to larvae. The protective effect of acacetin was also observed in CuSO₄ exposed zebrafish larvae by reducing malformation, mortality rate and oxidative stress. Meanwhile, the acacetin-protected larvae from CuSO₄ effects through the molecular mechanism by suppressing pro-inflammatory genes (COX-2, TNF-α and IL-1) and upregulating antioxidant genes (GPx, GST and GR). Overall, our findings suggest that acacetin can act as a protective barrier against CuSO₄-induced inflammation in an in-vivo zebrafish larval model.

Nimbin analog N2 alleviates high testosterone induced oxidative stress in CHO cells and alters the expression of Tox3 and Dennd1a signal transduction pathway involved in the PCOS zebrafish

Polycystic ovarian syndrome (PCOS) is a hormonal disorder that causes enlargement of ovaries and follicular maturation arrest, which lacks efficient treatment. N2, a semi-natural triterpenoid from the neem family, was already reported to have antioxidant and antiinflammatory properties in our previous report. This study investigated the anti-androgenic property of N2 on testosterone-induced oxidative stress in Chinese Hamster Ovarian cells (CHO) and PCOS zebrafish model. The testosterone exposure disrupted the antioxidant enzymes and ROS level and enhanced the apoptosis in both CHO cells and PCOS zebrafish. However, N2 significantly protected the CHO cells from ROS and apoptosis. N2 improved the Gonado somatic index (GSI) and upregulated the expression of the SOD enzyme in zebrafish ovaries. Moreover, the testosterone-induced follicular maturation arrest was normalized by N2 treatment in histopathology studies. In addition, the gene expression studies of Tox3 and Denndla in zebrafish demonstrated that N2 could impair PCOS condition. Furthermore, to confirm the N2 activity, the in-silico studies were performed against PCOS susceptible genes Tox3 and Dennd1a using molecular docking and molecular dynamic simulations. The results suggested that N2 alleviated the oxidative stress and apoptosis in-vitro and in-vivo and altered the expression of PCOS key genes.

Neuroprotective effect of Biochanin a against Bisphenol A-induced prenatal neurotoxicity in zebrafish by modulating oxidative stress and locomotory defects

Exogenous toxicants cause oxidative stress and damage to brain cells, resulting in inflammation. Neuroinflammation is important in the pathobiology of various neurological illnesses, including Alzheimer's disease (AD). In this context, Bisphenol A (BPA), a common toxin, causes oxidative damage and has been linked to neurological problems. An O-methylated isoflavone known as Biochanin A (5,7-dihydroxy-4'-methoxy-isoflavone, BCA) is considered to be a phytoestrogen, which is abundant in some legume plants and soy which have preventive effects against cancer, osteoporosis, menopausal symptoms and oxidative stress. However, the mechanism by which BCA protected the prenatal neurological stress are not known. So that, in this study we investigated the BCA neuroprotective effect against BPA-induced neuroinflammation in zebrafish embryo models. For this study, fertilized zebrafish embryos are exposed to BPA (1 µM) with or without BCA. Our finding suggested that BCA co-exposure prevented the depletion of antioxidant defense enzymes by BPA and reduced the production of intracellular ROS production, superoxide anion (O2-), lipid peroxidation (LPO), lactate dehydrogenase (LDH) and nitric oxide (NO) levels in the head that aided in safeguarding neuronal development. Baseline locomotion was rendered and a total distance was calculated to assess the motor function. Exposure to BCA increased acetylcholinestrase (AChE) and improved motor neuron functions. It also reduced the pro-inflammatory response expression and prevented neuroinflammation. Our study suggests that BCA has a positive role in the attenuation or amelioration of neuronal oxidative damage and locomotory behaviour induced by BPA.

Anti-Cancer and Anti-Inflammatory Activities of a Short Molecule, PS14 Derived from the Virulent Cellulose Binding Domain of Aphanomyces invadans, on Human Laryngeal Epithelial Cells and an In Vivo Zebrafish Embryo Model

In this study, the anti-cancer and anti-inflammatory activities of PS14, a short peptide derived from the cellulase binding domain of pathogenic fungus, Aphanomyces invadans, have been evaluated, in vitro and in vivo. Bioinformatics analysis of PS14 revealed the physicochemical properties and the web-based predictions, which indicate that PS14 is non-toxic, and it has the potential to elicit anti-cancer and anti-inflammatory activities. These in silico results were experimentally validated through in vitro (L6 or Hep-2 cells) and in vivo (zebrafish embryo or larvae) models. Experimental results showed that PS14 is non-toxic in L6 cells and the zebrafish embryo, and it elicits an antitumor effect Hep-2 cells and zebrafish embryos. Anticancer activity assays, in terms of MTT, trypan blue and LDH assays, showed a dose-dependent inhibitory effect on cell proliferation. Moreover, in the epithelial cancer cells and zebrafish embryos, the peptide challenge (i) caused significant changes in the cytomorphology and induced apoptosis; (ii) triggered ROS generation; and (iii) showed a significant up-regulation of anti-cancer genes including BAX, Caspase 3, Caspase 9 and down-regulation of Bcl-2, in vitro. The anti-inflammatory activity of PS14 was observed in the cell-free in vitro assays for the inhibition of proteinase and lipoxygenase, and heat-induced hemolysis and hypotonicity-induced hemolysis. Together, this study has identified that PS14 has anti-cancer and anti-inflammatory activities, while being non-toxic, in vitro and in vivo. Future experiments can focus on the clinical or pharmacodynamics aspects of PS14.

Deacetyl epoxyazadiradione protects aminoglycoside antibiotic-induced renal cell apoptosis, in vitro

Aminoglycoside antibiotics such as gentamicin are used frequently to treat bacterial infections in humans. Excessive consumption of these antibiotics lead to renal dysfunction. One of the factors contributing to renal dysfunction is oxidative damage, which causes apoptosis. Hence, this study investigates the effect of the antioxidant compound deacetyl epoxyazadiradione (DEA) in reducing cell death induced by gentamicin treatment in kidney cells (Madin-Darby canine kidney cells). The antioxidant experiments showed that reactive oxygen species level is decreased up to 27.06 ± 0.18% in 150 µM of DEA treatment. At this concentration, the activity of antioxidant enzymes such as superoxide dismutase increased from 0.4 ± 0.04 to 1.46 ± 0.05 µmol/min/L and catalase increased from 7.48 ± 0.39 to 17.6 ± 0.74 U/mg. The relative folds of gene expression of mitochondrial enzymes such as GST, GPx and GR restored from 0.596 ± 0.019, 0.521 ± 0.013 and 0.775 ± 0.014 to 0.866 ± 0.013, 0.669 ± 0.015 and 0.8615 ± 0.028, respectively. Consequently, the percentage of cell viability increases upto 91.8 ± 2.01 from 61.93 ± 1.63 with much less fragmentation in genomic DNA. Additionally, molecular docking results showed that DEA could bind to Bax, Bcl- 2, Caspase- 3 and Caspase- 9 proteins. These results indicate that DEA could reduce cell apoptosis by reducing oxidative stress due to antibiotics and interrupting the apoptotic signal pathway in kidney cells.

Withaferin A targets the membrane of Pseudomonas aeruginosa and mitigates the inflammation in zebrafish larvae; an in vitro and in vivo approach

Infections due to multidrug-resistant Pseudomonas aeruginosa are prevalent among patients with cystic fibrosis. The emergence of antibiotic-resistant pathogens necessitated the development of novel low-risk natural antibacterial compounds. Herbal medicines are used from dates of the origin of mankind and still serve their purpose as therapeutic agents. We demonstrated the antibacterial activity of Withaferin A extracted from the traditional herb, ashwagandha or winter cherry (Withania somnifera). Withaferin A exhibits strong antibacterial activity against P. aeruginosa with a minimum inhibitory concentration of 60 μM and minimum bactericidal concentration of 80 μM. Results obtained from membrane stabilization assay and electron microscopic analysis showed that Withaferin A acts by damaging the cell membrane of P. aeruginosa. Additionally, we investigated oxidative stress and inflammatory response after Withaferin A treatment in P. aeruginosa infected zebrafish larvae model. The results indicate that the level of ROS, and its related lipid peroxidation and apoptosis were significantly reduced after treated with Withaferin A. Consequently, an increment in antioxidant enzymes level such as superoxide dismutase (SOD) and catalase (CAT) was observed. Macrophage localization experiment showed a smaller number of localized macrophages in zebrafish, which indicates the reduction in inflammatory response. In conclusion, Withaferin A could serve as an alternative natural product in the treatment of infections caused by P. aeruginosa.

Intercellular communication and social behaviors in mycobacteria

Cell-to-cell communication is a fundamental process of bacteria to exert communal behaviors. Sputum samples of patients with cystic fibrosis have often been observed with extensive mycobacterial genetic diversity. The emergence of heterogenic mycobacterial populations is observed due to subtle changes in their morphology, gene expression level, and distributive conjugal transfer (DCT). Since each subgroup of mycobacteria has different hetero-resistance, they are refractory against several antibiotics. Such genetically diverse mycobacteria have to communicate with each other to subvert the host immune system. However, it is still a mystery how such heterogeneous strains exhibit synchronous behaviors for the production of quorum sensing (QS) traits, such as biofilms, siderophores, and virulence proteins. Mycobacteria are characterized by division of labor, where distinct sub-clonal populations contribute to the production of QS traits while exchanging complimentary products at the community level. Thus, active mycobacterial cells ensure the persistence of other heterogenic clonal populations through cooperative behaviors. Additionally, mycobacteria are likely to establish communication with neighboring cells in a contact-independent manner through QS signals. Hence, this review is intended to discuss our current knowledge of mycobacterial communication. Understanding mycobacterial communication could provide a promising opportunity to develop drugs to target key pathways of mycobacteria.

Deacetylated nimbin analog N2 fortifies alloxan-induced pancreatic β-cell damage in insulin-resistant zebrafish larvae by upregulating phosphoenolpyruvate carboxykinase (PEPCK) and insulin levels

This study aims to evaluate the protective behaviour of N2, a semi-natural analog of nimbin, for its anti-diabetic efficacy against alloxan-induced oxidative damage and β-cell dysfunction in in-vivo zebrafish larvae. A 500 μM of alloxan was exposed to zebrafish larvae for 24 h to induce oxidative stress in the pancreatic β-cells and co-exposed with N2 to study the protection of N2 by inhibiting ROS by DCFH-DA, DHE and NDA staining along with Cellular damage, apoptosis and lipid peroxidation. The zebrafish was further exposed to 500 μM alloxan for 72 h to induce β-cell destruction along with depleted glucose uptake and co-exposed to N2 to study the protective mechanism. Glucose levels were estimated, and PCR was used to verify the mRNA expression of phosphoenolpyruvate carboxykinase (PEPCK) and insulin. Alloxan induced (24 h) oxidative stress in the pancreatic β-cells in which N2's co-exposure inhibited ROS by eliminating O^-₂ radicals and restoring the glutathione levels, thus preventing cellular damage and lipid peroxidation. The zebrafish exposed to 500 μM alloxan for 72 h was observed with β-cell destruction along with depleted glucose uptake when stained with 2NBDG, wherein N2 was able to protect the pancreatic β-cells from oxidative damage, promoted high glucose uptake and reduced glucose levels. N2 stimulated insulin production and downregulated PEPCK by inhibiting gluconeogenesis, attenuating post-prandial hyperglycemia. N2 may contribute to anti-oxidant protection against alloxan-induced β-cell damage and anti-hyperglycemic activity, restoring insulin function and suppressing PEPCK expression.

Deacetylepoxyazadiradione Derived from Epoxyazadiradione of Neem (Azadirachta indica A. Juss) Fruits Mitigates LPS-Induced Oxidative Stress and Inflammation in Zebrafish Larvae

Reactive oxygen species (ROS) produced by cell metabolism have a duplex role in oxidation and inflammation reactions which involve cell damage or repair responses. Excess ROS production has detrimental effects on the survival of cells. We examined the protective effect of a semi-natural compound NF2 (deacetylepoxyazadiradione), for its protective activity against free radical-mediated stress and inflammatory response to lipopolysaccharide (LPS) using zebrafish larvae. Preliminary antioxidant assays indicated an increase in scavenging of free radicals from NF2 than NF1 (Epoxyazadiradione) in a concentration-dependent manner. Cell cytotoxicity was determined using rat myoblast cell lines (L6), and more than 95 % of cell viability was obtained. Zebrafish developmental toxicity test indicated that NF2 is not toxic even at 150 μM. The percentage of ROS, lipid peroxidation, nitric oxide and apoptosis were reduced significantly in NF2 treated LPS-stressed zebrafish larvae. The reduced number of employed macrophages on NF2 treatment was observed in neutral red dye-marked macrophage localization images. Relative expression of antioxidant genes in zebrafish larvae after treatment with NF2 is significantly increased. The RT-PCR quantification of antioxidant and anti-inflammatory gene expression indicated decreased relative folds of pro-inflammatory cytokines, iNOS and increased relative folds of mitochondrial antioxidant genes (GR, GST and GPx) in LPS stressed zebrafish larvae after treatment with NF2. From the overall obtained results, it can be concluded that NF2 reduced the oxidative stress and inflammatory response by scavenging free radicals caused by LPS.

Serine O-acetyltransferase derived NV14 peptide reduces cytotoxicity in H2O2 induced MDCK cells and inhibits MCF-7 cell proliferation through caspase gene expression

BACKGROUND

Most of the bioactive peptides exhibit antioxidant effect and do elicit inhibitory effect on proliferation of cancer cells. This study investigates the in-vitro antioxidant and anti-cancer properties of NV14 peptide, derived from serine O-acetyltransferase (SAT) of spirulina, Arthrospira platensis.

METHODS

The anti-cancer effect of the peptide was evaluated using human adenocarcinoma epithelial cells (MCF-7), while the anti-oxidant potential, as in reduction in ROS concentration, has been established using the H₂O₂-exposed, Madin-Darby canine kidney (MDCK) cells. The outcome of the in vitro analyses has been evaluated by in silico molecular docking analyses.

RESULTS

The peptide, dose-dependently, reduced oxidative stress as well as cell proliferation. Besides, based on the binding scores between NV14 peptide and the important proteins associated with apoptosis and antioxidant defense, it is evident that the peptide has antioxidant and anti-cancer effect, in vitro.

CONCLUSIONS

Together, this study demonstrates that NV14 has a potent antioxidant and anti-cancer capability; however, further direction needs to be focused on clinical or pharmacodynamics aspects.

Amelioration of acrylamide induced neurotoxicity by benzo[b]thiophene analogs via glutathione redox dynamics in zebrafish larvae

Acrylamide is a thermal process contaminant, which gets global attention due to its neurotoxic nature and its omnipresence in carbohydrate-rich foods. Chronic exposure to acrylamide leads to neuronal deterioration and motor dysfunction. Acrylamide could severely affect the antioxidant defense system, especially in the developing brain leading to premature neurological disorders. Acrylamide forms adduct in presynaptic neurons leading to neuroinflammation which is also a factor to consider. In this present study, we have explored whether our benzo[b]thiophene analogs, 1-(3-hydroxybenzo[b]thiophen-2-yl) ethanone (BP) and 1-(3-hydroxybenzo[b]thiophen-2-yl) propan-1-one hydrate (EP) with antioxidant activity, could inhibit the acrylamide-induced neurotoxicity-like behavior in zebrafish larvae. The experiment was set up to expose 3 days post fertilized (dpf) larvae to acrylamide (0.75 mM) for 3 days with or without compounds (80 µM). Locomotion behavioral analysis, antioxidants, glutathione, and acetylcholineesterase activity in the head region were analyzed after one day of the experimental procedure. We witnessed a restoration effect on glutathione redox dynamics. Since glutathione plays a crucial role in the detoxification of acrylamide, it is necessary to maintain the glutathione redox cycle to eliminate acrylamide from the body. BP and EP reduced the pro-inflammatory transcript in the head, which correlates with the reduction in oxidative stress. Finally, BP and EP showed a positive effect on synaptic vesicle cycling transcript and partially restores the motor neuron response to stimuli. Findings in this study showed the ability of compound BP and EP possess therapeutic value in oxidative stress-associated neurological disorders.

Daidzein normalized gentamicin-induced nephrotoxicity and associated pro-inflammatory cytokines in MDCK and zebrafish: Possible mechanism of nephroprotection

This study investigates the therapeutic activity of daidzein, an isoflavone that occurs naturally in plants and herbs, against gentamicin-induced nephrotoxicity in Madin-Darby canine kidney (MDCK) cells in-vitro and zebrafish model in-vivo. The in-vitro studies revealed that daidzein protected MDCK cells from gentamicin-induced inflammation by suppressing oxidative stress and apoptosis. The zebrafish were divided into groups and injected with gentamicin (140 mg/mL) to induce nephrotoxic conditions. After injection, renal dysfunction, nitric oxide production, antioxidant consumption, exaggerated apoptosis, and inflammation were all observed in the zebrafish model. We also observed that during kidney inflammation in zebrafish, pro-inflammatory cytokines such as cyclooxygenase (COX-2), tumor necrosis factor (TNF-α), and interleukin-1β (IL-1β) are upregulated. Furthermore, daidzein treatment after gentamicin injection showed a strong protective anti-inflammatory effect. Daidzein activity was associated with an increase in antioxidant biomarkers such as superoxide dismutase (SOD) and glutathione reductase (GSH), whereas lipid peroxidation (LPO) and nitric oxide (NO) production were decreased in a dose-dependent factor. Moreover, histopathological alteration caused by gentamicin in zebrafish kidneys was normalized due to daidzein treatment. Daidzein also downregulated the pro-inflammatory cytokines gene expression in gentamicin-induced kidney inflammation in zebrafish. These results revealed that daidzein could potentially prevent nephrotoxic conditions through pro-inflammatory cytokines inhibition and its antioxidant property.

Embryonic exposure to butylparaben and propylparaben induced developmental toxicity and triggered anxiety-like neurobehavioral response associated with oxidative stress and apoptosis in the head of zebrafish larvae

Parabens are synthetic antimicrobial compounds used as a preservative for extending the shelf life of food, pharmaceutical and cosmetic products. The alkyl chain length of the paraben esters positively correlates with their antimicrobial property. Hence, long-chain paraben esters, namely butylparaben and propylparaben, are used in combination as they have better solubility and antimicrobial efficacy. Extensive use of parabens has now resulted in the ubiquitous presence of these compounds in various human and environmental matrices. During early life, exposure to environmental contaminants is known to cause oxidative-stress mediated apoptosis in developing organs. The brain being one of the high oxygen-consuming, metabolically active and lipid-rich organ, it is primarily susceptible to reactive oxygen species (ROS) and lipid peroxidation (LP) induced neuronal cell death. The primary cause for the impairment in cognitive and emotional neurobehvioural outcomes in neurodegenerative disease was found to be associated with neuronal apoptosis. The present study aimed to study butylparaben and propylparaben's effect on zebrafish during early embryonic stages. Besides this, the association between alteration in anxiety-like neurobehavioral response with oxidative stress and antioxidant status in head region was also studied. The study results showed variation in the toxic signature left by butylparaben and propylparaben on developmental parameters such as hatching rate, survival and non-lethal malformations in a time-dependent manner. Data from the light-dark preference test showed embryonic exposure to butylparaben and propylparaben to trigger anxiety-like behavior in zebrafish larvae. In addition, a significant increase in intracellular ROS and LP levels correlated with suppressed antioxidant enzymes: superoxide dismutases (SOD), catalases (CAT), Glutathione peroxidase (GPx), glutathione S-transferase (GST), and Glutathione (GSH) activity in the head region of the zebrafish larvae. Acetylcholinesterase (AChE) activity was also suppressed in the exposed groups, along with increased nitric oxide production. The overall observations show increased oxidative stress indices correlating with upregulated expression of apoptotic cells in a dose-dependent manner. Collectively, our findings reveal butylparaben and propylparaben as an anxiogenic neuroactive compound capable of inducing anxiety-like behavior through a mechanism involving oxidative-stress-induced apoptosis in the head of zebrafish larvae, which suggests a potential hazard to the early life of zebrafish and this can be extrapolated to human health as well.

Pro-inflammatory cytokine molecules from Boswellia serrate suppresses lipopolysaccharides induced inflammation demonstrated in an in-vivo zebrafish larval model

BACKGROUND

Boswellia serrate is an ancient and highly valued ayurvedic herb. Its extracts have been used in medicine for centuries to treat a wide variety of chronic inflammatory diseases. However, the mechanism by which B. serrata hydro alcoholic extract inhibited pro-inflammatory cytokines in zebrafish (Danio rerio) larvae with LPS-induced inflammation remained unknown.

METHODS

LC-MS analysis was used to investigate the extract's phytochemical components. To determine the toxicity of B. serrata extract, cytotoxicity and embryo toxicity tests were performed. The in-vivo zebrafish larvae model was used to evaluate the antioxidant and anti-inflammatory activity of B. serrata extract.

RESULTS

According to an in silico study using molecular docking and ADMET, the compounds acetyl-11-keto-boswellic and 11-keto-beta-boswellic acid present in the extract had higher binding affinity for the inflammatory specific receptor, and it is predicted to be an orally active molecule. In both in-vitro L6 cells and in-vivo zebrafish larvae, 160 µg/mL concentration of extract caused a high rate of lethality. The extract was found to have a protective effect against LPS-induced inflammation at concentrations ranged between 10 and 80 µg/mL. In zebrafish larvae, 80 µg/mL of treatment significantly lowered the level of intracellular ROS, apoptosis, lipid peroxidation, and nitric oxide. Similarly, zebrafish larvae treated with B. serrata extract (80 µg/mL) showed an increased anti-inflammatory activity by lowering inflammatory specific gene expression (iNOS, TNF-α, COX-2, and IL-1).

CONCLUSIONS

Overall, our findings suggest that B. serrata can act as a potent redox scavenger against LPS-induced inflammation in zebrafish larvae and an inhibitor of specific inflammatory genes.