Inhibitory effect of food-functioned phytochemicals on dysregulated inflammatory pathways triggered by SARS-CoV-2: a mechanistic review

Inflammatory cascades of the dysregulated inflammatory pathways in COVID-19 can cause excessive production of pro-inflammatory cytokines and chemokines leading to cytokine storm syndrome (CSS). The molecular cascades involved in the pathways may be targeted for discovery of new anti-inflammatory agents. Many plant extracts have been used clinically in the management of COVID-19, however, their immunosuppressive activities were mainly investigated based on in silico activity. Dietary flavonoids of the extracts such as quercetin, luteolin, kaempferol, naringenin, isorhamnetin, baicalein, wogonin, and rutin were commonly identified as responsible for their inhibitory effects. The present review critically analyzes the anti-inflammatory effects and mechanisms of phytochemicals, including dietary compounds against cytokine storm (CS) and hyperinflammation via inhibition of the altered inflammatory pathways triggered by SARS-CoV-2, published since the emergence of COVID-19 in December 2019. Only a few phytochemicals, mainly dietary compounds such as nanocurcumin, melatonin, quercetin, 6-shagoal, kaempferol, resveratrol, andrographolide, and colchicine have been investigated either in in silico or preliminary clinical studies to evaluate their anti-inflammatory effects against COVID-19. Sufficient pre-clinical studies on safety and efficacy of anti-inflammatory effects of the phytochemicals must be performed prior to proper clinical studies to develop them into therapeutic adjuvants in the prevention and treatmemt of COVID-19 symptoms.

Fibroblast-derived PI16 sustains inflammatory pain via regulation of CD206+ myeloid cells

Originally identified in fibroblasts, Protease Inhibitor (PI)16 was recently shown to be crucial for the development of neuropathic pain via effects on blood-nerve barrier permeability and leukocyte infiltration, though its impact on inflammatory pain has not been established. Using the complete Freund's Adjuvant inflammatory pain model, we show that Pi16-/- mice are protected against sustained inflammatory pain. Accordingly, intrathecal delivery of a PI16 neutralizing antibody in wild-type mice prevented sustained CFA pain. In contrast to neuropathic pain models, we did not observe any changes in blood-nerve barrier permeability due to PI16 deletion. Instead, Pi16-/- mice display reduced macrophage density in the CFA-injected hindpaw. Furthermore, there was a significant bias toward CD206hi (anti-inflammatory) macrophages in the hindpaw and associated dorsal root ganglia. Following CFA, intrathecal depletion of CD206+ macrophages using mannosylated clodronate liposomes promoted sustained pain in Pi16-/- mice. Similarly, an IL-10 neutralizing antibody also promoted sustained CFA pain in the Pi16-/ when administered intrathecally. Collectively, our results point to fibroblast-derived PI16 mediating substantial differences in macrophage phenotype in the pain neuroaxis under conditions of inflammation. The co-expression of PI16 alongside fibroblast markers in human DRG raise the likelihood that a similar mechanism operates in human inflammatory pain states. Collectively, our findings may have implications for targeting fibroblast-immune cell crosstalk for the treatment of chronic pain.

Immunomodulatory effects and mechanisms of the extracts and secondary compounds of Zingiber and Alpinia species: a review

Zingiber and Alpinia species (family: Zingiberaceae) are popularly used in food as spices and flavoring agents and in ethnomedicine to heal numerous diseases, including immune-related disorders. However, their ethnomedicinal uses have not been sufficiently supported by scientific investigations. Numerous studies on the modulating effects of plants and their bioactive compounds on the different steps of the immune system have been documented. This review aimed to highlight up-to-date research findings and critically analyze the modulatory effects and mechanisms of the extracts and secondary compounds of several Zingiber and Alpinia species, namely, Zingiber officinale Roscoe, Z. cassumunar Roxb., Z. zerumbet (L.) Roscoe ex Sm., Alpinia galanga Linn., A. conchigera Griff, A. katsumadai Hayata, A. oxyphylla Miq., A. officinarum Hance, A. zerumbet (Pers.) Burtt. et Smith, and A. purpurata (Viell.) K. Schum. on the immune system, particularly via the inflammation-related signaling pathways. The immunomodulating activities of the crude extracts of the plants have been reported, but the constituents contributing to the activities have mostly not been identified. Among the extracts, Z. officinale extracts were the most investigated for their in vitro, in vivo, and clinical effects on the immune system. Among the bioactive metabolites, 6-, 8-, and 10-gingerols, 6-shogaol, and zerumbone from Zingiber species and cardamomin, 1'-acetoxychavicol acetate, yakuchinone, rutin, 1,8-cineole, and lectin from Alpinia species have demonstrated strong immunomodulating effects. More experimental studies using cell and animal models of immune-related disorders are necessary to further understand the underlying mechanisms, together with elaborate preclinical pharmacokinetics, pharmacodynamics, bioavailability, and toxicity studies. Many of these extracts and secondary metabolites are potential candidates for clinical development in immunomodulating agents or functional foods to prevent and treat chronic inflammatory disorders.

Antiviral effects of phytochemicals against severe acute respiratory syndrome coronavirus 2 and their mechanisms of action: A review

The worldwide spreading of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a serious threat to health, economic, environmental, and social aspects of human lives. Currently, there are no approved treatments that can effectively block the virus although several existing antimalarial and antiviral agents have been repurposed and allowed use during the pandemic under the emergency use authorization (EUA) status. This review gives an updated overview of the antiviral effects of phytochemicals including alkaloids, flavonoids, and terpenoids against the COVID-19 virus and their mechanisms of action. Search for natural lead molecules against SARS-CoV-2 has been focusing on virtual screening and in vitro studies on phytochemicals that have shown great promise against other coronaviruses such as SARS-CoV. Until now, there is limited data on in vivo investigations to examine the antiviral activity of plants in SARS-CoV-2-infected animal models and the studies were performed using crude extracts. Further experimental and preclinical investigations on the in vivo effects of phytochemicals have to be performed to provide sufficient efficacy and safety data before clinical studies can be performed to develop them into COVID-19 drugs. Phytochemicals are potential sources of new chemical leads for the development of safe and potent anti-SARS-CoV-2 agents.

Immunosuppressive Effects of Annona muricata L. Leaf Extract on Cellular and Humoral Immune Responses in Male Wistar Rats

Background:

Annona muricata L. (Annonaceae) (AM) 's remarkable anti-inflammatory and anti-cancer activities make it a targeted plant to be explored for its immunomodulatory properties. Traditional practitioners have employed various components of AM to cure a variety of ailments, including cancer, diabetes, and inflammation.

Objective:

The present study evaluated the immunosuppressive effects of 80% ethanol extract of of AM leaves in male Wistar rats on different parameters of humoral and cellular immune responses.

Methods:

AM leaf extract (AMLE) was analyzed using UHPLC-MS/MS to profile its secondary metabolites. AMLE was rich in polyphenols which include (epi)catechin-(epi)catechin-(epi)catechin, caffeic acid, coumaroylquinic acid, hyperin, kaempferol, quinic acid and rutin. The rats were administered 100, 200 and 400 mg/kg bw of the extract daily for 14 days. The effects of AMLE on innate immune responses were determined by evaluating phagocytosis, neutrophils migration, reactive oxygen species (ROS) release, CD11b/CD18 integrin expression, and ceruloplasmin, lysozyme and myeloperoxidase (MPO) levels. The adaptive immune parameters were evaluated by immunizing the rats with sheep red blood cells (sRBC) on day 0 and administered orally with AMLE for 14 days.

Results:

AMLE established significant immunosuppressive effects on the innate immune parameters by inhibiting the neutrophil migration, ROS production, phagocytic activity and expression of CD11b/CD18 integrin in a dose-dependent pattern. AMLE also suppressed ceruloplasmin, MPO and lysozyme expressions in the rat plasma dose-dependently. AMLE dose-dependently inhibited T and B lymphocytes proliferation, Th1 and Th2 cytokine production, CD4+ and CD8+ co-expression in splenocytes, immunoglobulins (IgM and IgG) expression and the sRBC-induced swelling rate of rat paw in delayed-type hypersensitivity (DTH).

An updated and comprehensive review on the ethnomedicinal uses, phytochemistry, pharmacological activity and toxicological profile of Tinospora crispa (L.) Hook. f. & Thomson

Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae) is a plant indigenous to Africa and South-East Asia. It is widely used in ethnomedicine to alleviate various diseases including hypertension, diabetes, rheumatism, jaundice, inflammation, fever, fractures, scabies, and urinary disorders. A total of 167 phytoconstituents, belonging to 12 different chemical categories, including alkaloids, flavonoids, terpenoids, and phenolic compounds have thus far been isolated from various parts of T. crispa. Numerous in vitro and in vivo investigations have already established the antidiabetic, anticancer, antiparasitic, antimicrobial, immunomodulatory, hepatoprotective, analgesic, antipyretic, antihyperuricemic, and pesticidal activity of this plant, as well as its effects on the cardiac and the central nervous system. Most pharmacological investigations to date have been carried out on plant extracts and fractions. The exact identity of the phytoconstituents responsible for the observed biological effects and their mode of action at the molecular level are yet to be ascertained. Toxicological studies have demonstrated that T. crispa is relatively safe, although dose-dependent hepatotoxicity is a concern at high doses. This review presents a comprehensive update and analysis on studies related to the ethnomedicinal uses, phytochemistry, pharmacological activity and toxicological profile of T. crispa. It provides some critical insights into the current scientific knowledge on this plant and its future potential in pharmaceutical research.

Correlation between Antero-posterior Diameter and Vertical Diameter of Both Ends of Fully Ossified Dry Human Clavicle

Clavicle is an upper limb locomotory bone which helps in formation of pectoral girdle and connected the upper limb with axial skeleton. There is no baseline data of clavicle in contrast to demographic variation in our country, so the study was designed to obtain baseline data on clavicle for anthropological, forensic and clinical use. This descriptive cross-sectional study was done among 150 (65 right and 85 left) fully ossified dry human clavicle in Mymensingh Medical College, Mymensingh, Bangladesh from January 2020 to December 2020. Sample was collected by the help of nonrandom purposive sampling technique from Department of Anatomy of Mymensingh Medical College and Community Based Medical College, Bangladesh, Mymensingh. The parameters were the antero-posterior diameter and vertical diameter of sternal and acromial ends of clavicle, measured with the help of digital vernier slide caliper and expressed in millimeter. In the current study the mean±SD antero-posterior diameter of sternal end of 65 clavicles of right side was 21.97±2.889mm and 85 clavicles of left side were 20.30±3.459mm. The mean±SD antero-posterior diameter of acromial end of 65 right sided clavicles was 21.96±5.161mm and 85 clavicles of left side were 21.00±4.002mm. Correlation was done in between antero-posterior diameter and vertical diameter of sternal end of clavicle and the differences were highly significant on both sides. Similarly, when correlation was done for the acromial end of clavicle the difference was found non-significant on right side and highly significant on left side.

Magnoflorine from Tinospora crispa upregulates innate and adaptive immune responses in Balb/c mice

Magnoflorine shows a diverse range of pharmacological actions, including immunomodulatory, antioxidant and neuropharmacological activities. However, its effects on the immune responses in animal studies have not been reported. In this study, magnoflorine isolated from Tinospora crispa, at doses of 25, 50 and 100 mg/kg was administered to male Balb/c mice daily for 14 days to evaluate its effect on innate immune responses, while for evaluation of adaptive immune responses, on day 0 the mice were injected intraperitoneally with sheep red blood cells (sRBC) and treated orally with the various doses of magnoflorine for the same duration. The effects of magnoflorine on phagocytosis, myeloperoxidase (MPO) activity, lysozyme serum level, nitric oxide (NO) production, CD4+ and CD8+ cells population, T and B lymphocytes proliferation, activated T cells cytokines production, antibodies levels and delayed type hypersensitivity (DTH) were determined. Magnoflorine dose-dependently stimulated NO production, E. coli engulfment by neutrophils and peritoneal macrophages, MPO activity and lysozyme serum level in treated mice. Magnoflorine at 100 mg/kg exhibited comparable stimulation of B cell production compared to levamisole at 2.5 mg/kg. It also significantly increased CD4+ and CD8+ cells population, upregulated the Th1 (IFN-γ, IL-2 and TNF-α) and Th2 (IL-4 and IL-6) cytokines in a dose-dependent manner. At similar concentrations, magnoflorine also exhibited a strong dose-dependent stimulation on DTH reaction and upregulation of immunoglobulins (IgG and IgM) production in mice immunized with sRBC. The strong upregulation of innate and adaptive immune responses indicates that magnoflorine has potential to be developed into an effective immunostimulant.

An insight into the anti-ulcerogenic potentials of medicinal herbs and their bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Peptic ulcer disease (PUD) ranks top among the most prominent gastrointestinal problems prevalent around the world. Long-term use of non-steroidal anti-inflammatory drugs, pathogenic infection by Helicobacter pylori, imbalances between gastrointestinal regulatory factors and pathological hyperacidity are major contributors towards the development of peptic ulcers. Although synthetic drugs of multiple pharmacological classes are abundantly available, inadequacy of such agents in ensuring complete recovery in not uncommon. Therefore, pharmacological explorations of herbal products including plant extracts and their respective isolated phytoconstituents, for potential gastroprotective and antiulcer properties, are regular practice among the scientific community. Moreover, the historical preferences of a significant share of world population towards herbal-based medication over modern synthetic drugs also contribute significantly to such endeavors.

AIM OF THE REVIEW

This review has endeavored to present ethnomedicinal and pharmacological prospects of a significant number of authenticated plant species in terms of their capacity to exert gastroprotection and antiulcer activities both in vitro and in vivo. The information delineated along the way was further subjected to critical analysis to ascertain the possible future prospects of such findings into designing plant-derived products in future for the treatment of peptic ulcer.

MATERIALS AND METHODS

Electronic version of prominent bibliographic databases, including Google Scholar, PubMed, Scopus, ScienceDirect, Wiley Online Library, SpringerLink, Web of Science, and MEDLINE were explored extensively for the identification and compilation of relevant information. The plant names and respective family names were verified through the Plant List (version 1.1) and World Flora Online 2021. All relevant chemical structures were verified through PubChem and SciFinder databases and illustrated with ChemDraw Ultra 12.0.

RESULTS

A colossal number of 97 plant species categorized under 58 diverse plant families have been discussed in the review for their gastroprotective and antiulcer properties. In vivo illustrations of the pharmacological properties were achieved for almost all the species under consideration. 29 individual phytoconstituents from these sources were also characterized with similar pharmacological potentials. Majority of the plant extracts as well as their constituents were found to exert their gastroprotective effects through antioxidative pathway featuring both enzymatic and nonenzymatic mechanism. Moreover, active inhibition of acid secretion, upregulation of gastroprotective mediators and downregulation of pro-inflammatory cytokines, were also associated with a prominent number of plants or products thereof.

CONCLUSIONS

Comparative evaluations of the plant sources for their antiulcer activities, both as individual and as combination formulations, are necessary to be conducted in human subjects under properly regulated clinical conditions. Moreover, the efficacy and safety of such products should also be evaluated against those of the currently available treatment options. This will further facilitate in ascertaining their suitability and superiority, if any, in the treatment of peptic ulcer diseases. Implementation of these endeavors may eventually lead to development of more efficient treatment options in the future.

Allium vegetables: Traditional uses, phytoconstituents, and beneficial effects in inflammation and cancer

The genus Allium comprises of at least 918 species; the majority grown for dietary and medicinal purposes. This review describes the traditional uses, phytoconstituents, anti-inflammatory and anticancer activity, and safety profile of six main species, namely Allium sativum L. (garlic), Allium cepa L. (onions), Allium ampeloprasum L. (leek), Allium fistulosum L. (scallion), Allium schoenoprasum L. (chives) and Allium tuberosum Rottler (garlic chives). These species contain at least 260 phytoconstituents; mainly volatile compounds-including 63 organosulfur molecules-, saponins, flavonoids, anthocyanins, phenolic compounds, amino acids, organic acids, fatty acids, steroids, vitamins and nucleosides. They have prominent in vitro anti-inflammatory activity, and in vivo replications of such results have been achieved for all except for A. schoenoprasum. They also exert cytotoxicity against different cancer cell lines. Several anticancer phytoconstituents have been characterized from all except for A. fistulosum. Organosulfur constituents, saponins and flavonoid glycosides have demonstrated anti-inflammatory and anticancer activity. Extensive work has been conducted mainly on the anti-inflammatory and anticancer activity of A. sativum and A. cepa. The presence of anti-inflammatory and anticancer constituents in these two species suggests that similar bioactive constituents could be found in other species. This provides future avenues for identifying new Allium-derived anti-inflammatory and anticancer agents.

Noonan Syndrome Presenting with Stunted Growth: A Case Report

Noonan syndrome is a genetic disorder of autosomal dominant inheritance that prevents normal development in various parts of the body. A spontaneous mutation without any family history may also result in the condition. Noonan syndrome can affect normal growth. Birth weight may be normal, but growth slows over time. The growth spurt usually seen during the teenage years may be delayed, and bone maturity also is delayed. In this case A 13 year's male admitted inpatient Department of Endocrinology, Mymensingh Medical College Hospital in April 2021 with not attaining appropriate height and delayed development of secondary sexual characteristics. His birth weight was normal; gestational and neonatal history was uneventful. He was diagnosed with severe pulmonary stenosis at four years and underwent cardiac surgery at his four and eleven years. He was noted to have growth failure from the age of 9 years onward. He had no family history of such type of disease. On examination, he was short statured, underweight, having an upper: lower segment ratio of 1.05 with an arm span of 126cm. He had craniosynostosis, high arched palate, the thick helix of ears (outer rim), small, upturned nose, depressed broad nose, deeply grooved philtrum, keratosis pilaris of the face and upper arm, slant eyes with proptosis, keloid scar over mid-chest, widely spaced nipple, shield chest, pectus excavatum and cubitus valgus. His sexual maturation score was A1, P1, B1. He had pulmonary stenosis with pulmonary hypertension. He had mild microcytic anemia with normal liver, renal, blood glucose, and calcium profile. His bone age was delayed (9 years), thyroid function was normal. The growth hormone dynamic test after clonidine stimulation was normal. His karyotype was 46XY. We have considered giving recombinant growth hormone therapy to accelerate his height.

Mechanistic insight into immunomodulatory effects of food-functioned plant secondary metabolites

Medicinally important plant-foods offer a balanced immune function, which is essential for protecting the body against antigenic invasion, mainly by microorganisms. Immunomodulators play pivotal roles in supporting immune function either suppressing or stimulating the immune system's response to invading pathogens. Among different immunomodulators, plant-based secondary metabolites have emerged as high potential not only for immune defense but also for cellular immunoresponsiveness. These natural immunomodulators can be developed into safer alternatives to the clinically used immunosuppressants and immunostimulant cytotoxic drugs which possess serious side effects. Many plants of different species have been reported to possess strong immunomodulating properties. The immunomodulatory effects of plant extracts and their bioactive metabolites have been suggested due to their diverse mechanisms of modulation of the complex immune system and their multifarious molecular targets. Phytochemicals such as alkaloids, flavonoids, terpenoids, carbohydrates and polyphenols have been reported as responsible for the immunomodulatory effects of several medicinal plants. This review illustrates the potent immunomodulatory effects of 65 plant secondary metabolites, including dietary compounds and their underlying mechanisms of action on cellular and humoral immune functions in in vitro and in vivo studies. The clinical potential of some of the compounds to be used for various immune-related disorders is highlighted.

Role of neurotoxicants in the pathogenesis of Alzheimer's disease: a mechanistic insight

Alzheimer's disease (AD) is the most conspicuous chronic neurodegenerative syndrome, which has become a significant challenge for the global healthcare system. Multiple studies have corroborated a clear association of neurotoxicants with AD pathogenicity, such as Amyloid beta (Aβ) proteins and neurofibrillary tangles (NFTs), signalling pathway modifications, cellular stress, cognitive dysfunctions, neuronal apoptosis, neuroinflammation, epigenetic modification, and so on. This review, therefore, aimed to address several essential mechanisms and signalling cascades, including Wnt (wingless and int.) signalling pathway, autophagy, mammalian target of rapamycin (mTOR), protein kinase C (PKC) signalling cascades, cellular redox status, energy metabolism, glutamatergic neurotransmissions, immune cell stimulations (e.g. microglia, astrocytes) as well as an amyloid precursor protein (APP), presenilin-1 (PSEN1), presenilin-2 (PSEN2) and other AD-related gene expressions that have been pretentious and modulated by the various neurotoxicants. This review concluded that neurotoxicants play a momentous role in developing AD through modulating various signalling cascades. Nevertheless, comprehension of this risk agent-induced neurotoxicity is far too little. More in-depth epidemiological and systematic investigations are needed to understand the potential mechanisms better to address these neurotoxicants and improve approaches to their risk exposure that aid in AD pathogenesis.Key messagesInevitable cascade mechanisms of how Alzheimer's Disease-related (AD-related) gene expressions are modulated by neurotoxicants have been discussed.Involvement of the neurotoxicants-induced pathways caused an extended risk of AD is explicited.Integration of cell culture, animals and population-based analysis on the clinical severity of AD is addressed.

Ethnomedicinal uses, phytochemistry, pharmacological activities and toxicological profile of Glycosmis pentaphylla (Retz.) DC.: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Glycosmis pentaphylla (Retz.) DC. is a perennial shrub indigenous to the tropical and subtropical regions of India, China, Sri Lanka, Myanmar, Bangladesh, Indonesia, Malaysia, Thailand, Vietnam, Philippine, Java, Sumatra, Borneo and Australia. The plant is used extensively within these regions as a traditional medicine for the treatment of a variety of ailments including cough, fever, chest pain, anemia, jaundice, liver disorders, inflammation, bronchitis, rheumatism, urinary tract infections, pain, bone fractures, toothache, gonorrhea, diabetes, cancer and other chronic diseases.

AIM OF THE REVIEW

This review aims to present up-to-date information regarding the taxonomy, botany, distribution, ethnomedicinal uses, phytochemistry, pharmacology and toxicological profile of G. pentaphylla. The presented information was analyzed critically to understand current work undertaken on this species and explore possible future prospects for this plant in pharmaceutical research.

MATERIALS & METHODS

Bibliographic databases, including Google Scholar, PubMed, Web of Science, ScienceDirect, SpringerLink, Wiley Online Library, Semantic Scholar, Europe PMC, Scopus, and MEDLINE, were explored thoroughly for the collection of relevant information. The structures of phytoconstituents were confirmed with PubChem and SciFinder databases. Taxonomical information on the plant was presented in accordance with The Plant List (version 1.1).

RESULTS

Extensive phytochemical investigations into different parts of G. pentaphylla have revealed the presence of at least 354 secondary metabolites belonging to structurally diverse classes including alkaloids, amides, phenolic compounds, flavonoids, glycosides, aromatic compounds, steroids, terpenoids, and fatty derivatives. A large number of in vitro and in vivo experiments have demonstrated that G. pentaphylla had anticancer, antimutagenic, antibacterial, antifungal, anthelmintic, mosquitocidal, antidiabetic, antihyperlipidemic, anti-oxidant, anti-inflammatory, analgesic, antipyretic, anti-arsenicosis, and wound healing properties. Toxicological studies have established the absence of any significant adverse reactions and showed that the plant had a moderate safety profile.

CONCLUSIONS

G. pentaphylla can be suggested as a source of inspiration for the development of novel drugs, especially anticancer, antimicrobial, anthelmintic, and mosquitocidal agents. Moreover, bioassay-guided investigations into its diverse classes of secondary metabolites, especially the large pool of nitrogen-containing alkaloids and amides, promises the development of novel drug candidates. Future pharmacological studies into this species are also warranted as many of its traditional uses are yet to be validated scientifically.

Prevalence of Hepatitis B Virus Infection among Children with Liver Disease Admitted In Mymensingh Medical College Hospital

Hepatitis B virus infection is an important cause of liver disease. Hepatitis B Virus may present with varying degree of severity. In older children, 5-10% cases leading to chronic liver disease, cirrhosis and hepatocellular carcinoma. This descriptive cross sectional study was done to assess the prevalence of Hepatitis B Virus infection among hospitalized children with liver disease in pediatric department of Mymensingh Medical College Hospital, Bangladesh from December 2015 to October 2016. All the children of both sexes having age between six months to twelve years admitted in the pediatric ward with acute or chronic liver disease were included in this study by purposive sampling. A written consent was obtained from legal guardian of children before inclusion. Ethical clearance was obtained from competent authority. A detailed history was taken from parents in each case according to pre-designed questionnaire about demography of the patients and the risk factors of the liver disease. A thorough clinical examination and available relevant investigations like serological testing for HBV infection was done in all patients. We had figure out the seropositivity of HBV among patients having liver disease by doing HBsAg and Anti-HBc IgM. Progress of the patient was monitored by daily clinical examinations and by investigating HBsAg and Anti-HBc IgM. Finally data analysis was done by SPSS version 21.0. Among total 100 patients most (44%) patients were in 7-10 years old and most (62%) of the participants were male. Acute liver disease was 58% cases and chronic liver disease was 42% cases. HBsAg was positive in 1 case among acute liver disease and 5 cases among chronic cases. Total 6 (six) patients were found positive for HBsAg. Anti HBc IgM was positive in 4 patients among acute liver disease. Among these Anti HBc IgM positive (4) patients only one had both HBsAg and Anti HBc IgM positive. So, four patients were confirming suffered from acute viral hepatitis because they had anti HBc IgM positive. On the contrary 5 patients suffered from chronic hepatitis by hepatitis B because they were only HBsAg positive. So, in this study 9 patients (9%) were confirming suffered from HBV infection. Possible transmission factors of hepatitis B were history of (H/O) blood transfusion/trauma/parenteral injection, H/O umbilical sepsis, H/O maternal illness/infection during pregnancy. HBV still is a major cause of morbidity. All the children with liver disease should be routinely tested for HBV.

A Prospective Study of Deep Vein Thrombosis after Major Abdominal Surgery in a Tertiary Level Hospital

This prospective study was conducted to find the rate of deep and risk factors associated with vein thrombosis following major abdominal surgery in Sylhet MAG Osmani Medical College Hospital from 1st November 2017 to 30th April 2018. Total 103 patients aged above 20 years both male and female who got admitted in Department of Surgery, Sylhet MAG Osmani Medical College Hospital, Sylhet for their disease requiring routine and emergency major abdominal operation during the study period and fulfilling the inclusion and exclusion criteria were selected in this study. Informed written consent was obtained from the patients after full explanation of the purpose of the study. After full investigations and proper preparation of each patient for operative procedure major abdominal surgery were done. Peroperative findings were noted and post-operative period were followed up routinely. Duplex scanning was done on 3rd POD in all cases. The age of the patients ranged from 25 to 74 years with the mean age of 49.5±13.8 years. There were 60(58.3%) male and 43(41.7%) female. Deep vein thrombosis (DVT) developed in 5(4.9%) of cases and not developed in 98(95.1%) cases. All the five cases were confirmed by color duplex scan. DVT was detected in 2(3.3%) of the 60 males and 3(7.0%) of the 43 females undergoing major general surgical procedures. Among 63 patients in whom the duration of surgery was up to 2 hours, none developed DVT, while among the 40 patients in whom the duration of surgery lasted more than 2 hours, 5(12.5%) developed DVT. Among 23 patients in whom the surgery for malignancy was done, 4(17.4%) developed DVT, while among the 80 patients in whom surgery for non-malignancy, 1(1.2%) developed DVT. The Incidence of DVT in patients undergoing major abdominal surgery is 4.9%. Patients undergoing major abdominal surgery for malignancy and duration of operation greater than 2 hours have higher risk of developing DVT. But there is no significant increase in risk of development of DVT relation to age and sex; and also in patients on oral contraceptives, diabetes mellitus, obesity and smoking. Clinical findings alone cannot be relied upon for the diagnosis of DVT. The study has to be continued with larger sample size to get statistically significant results.

Salinity Influences Plant-Pest-Predator Tritrophic Interactions

Climate change-induced salinity intrusion into agricultural soils is known to negatively impact crop production and food security. However, the effects of salinity increase on plant-herbivore-natural enemy systems and repercussions for pest suppression services are largely unknown. Here, we examine the effects of increased salinity on communities of rice (Oryza sativa), brown planthopper (BPH), Nilaparvata lugens, and green mirid bug (GMB), Cyrtorhinus lividipennis, under greenhouse conditions. We found that elevated salinity significantly suppressed the growth of two rice cultivars. Meanwhile, BPH population size also generally decreased due to poor host plant quality induced by elevated salinity. The highest BPH density occurred at 2.0 dS/m salinity and declined thereafter with increasing salinity, irrespective of rice cultivar. The highest population density of GMB also occurred under control conditions and decreased significantly with increasing salinity. Higher salinity directly affected the rice crop by reducing plant quality measured with reference to biomass production and plant height, whereas inducing population developmental asynchrony between BPH and GMB observed at 2 dS/m salinity and potentially uncoupling prey-predator dynamics. Our results suggest that increased salinity has harmful effects on plants, herbivores, natural enemies, as well as plant-pest-predator interactions. The effects measured here suggest that the bottom-up effects of predatory insects on rice pests will likely decline in rice produced in coastal areas where salinity intrusion is common. Our findings indicate that elevated salinity influences tritrophic interactions in rice production landscapes, and further research should address resilient rice insect pest management combining multipests and predators in a changing environment.

Comparison of Nutritional Status of Children with Congenital Heart Diseases with Minor Illness of Other Children in a Tertiary Level Hospital

This cross sectional comparative analytical study was undertaken with the objectives to find out the nutritional status of children with congenital heart disease by anthropometric measurement and was compared it with those of children having minor illness and without any congenital heart disease in indoor and outdoor Department of Paediatrics of Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh from December 2015 to November 2016. Purposive sampling was done. One hundred children aged 6 to 60 months with congenital heart disease confirmed by echocardiogram were taken as Group A and one hundred children of same age and sex matched having minor illness and without any congenital heart disease were taken as Group B. Age of the patients ranged from 6 to 60 months. There was no obvious difference of socio-demographic status between two groups. Most of the patient (64.0%) had acyanotic congenital heart disease among them VSD was commonest (68.8%). Thirty-six percent (36.0%) patient had cyanotic congenital heart disease and among them Tetralogy of Fallots (83.3%) was commonest. There were significant differences regarding weight, height and MUAC values in between two Groups. Underweight (51%), Stunting (50%) and Wasting (29%) all were higher in congenital heart disease than that of Group B where they were 28%, 31% and 13% respectively and the differences were statistically significant (p<0.05). The findings of this study imply that malnutrition is very common among children with congenital heart disease. So, anthropometric measurement should be done in each and every child with congenital heart disease.

Bioactive metabolites of Blumea lacera attenuate anxiety and depression in rodents and computer-aided model

Blumea lacera is an edible plant with imperative medicinal values. However, the anxiolytic and antidepressant roles of B. lacera have not been well-explained. Therefore, the current study aims to explore the impending bioactive metabolites and roles of B. lacera methanol leaf extract (Me-BLL) in attenuating anxiety and depression through several experimental and computer-aided approaches. The chemical characterization of Me-BLL was performed through standard phytochemical and GC-MS analyses. To explore the neuropharmacological insights, Swiss albino mice were treated with Me-BLL at doses of 200-400 mg/kg, p.o. The anxiolytic effects were observed employing elevated plus maze (EPM), light-dark box (LDB), and hole-board (HBT) tests, while antidepressant effects were evaluated using forced swimming (FST) and tail suspension tests (TST). Diazepam (1 mg/kg, i.p.) and fluoxetine HCl (20 mg/kg, p.o.) were used as the reference standard. The phytochemical analyses revealed several bioactive metabolites, including higher contents of total phenolics and flavonoids. The EPM and LDB tests demonstrated an increased time spent in open arms and light box, and the HBT showed an increased number of head dipping, indicating the anxiolytic effects of Me-BLL. The TST and FST revealed a decrease in immobility time, meaning the persuasive antidepressant effects. The antioxidative effects of Me-BLL have also been observed prominently. Correspondingly, the computer-aided investigation confirmed several bioactive lead molecules. Specifically, thymol and cuminol revealed potential anxiolytic and antioxidant effects, while stigmast-5-en-3.beta.-ol and gamma-sitosterol possessed promising antidepressant effects. Taken these results as a base, the plant has imperative potentials in managing anxiety and depression-like disorders.

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822)

This investigation presents the food and feeding activity of and endangered riverine catfish Rita rita, during February 2017-January 2018. A total of 225 fish individuals was analyzed for stomach contents by characterizing the dominant food items and morphometric features. The results divulged ten major food items consumed, preferably fish scales and eggs, teleost fishes, copepods, cladocerans, rotifers, and mollusks. Total length and body weight of fish varied between 9-34 cm (20.53 ± 6.90 cm) and 10-400 g (9125.94 ± 102.07 g), respectively. The index of relative importance (IRI%) showed the importance of rotifers over the other food items. Morisita's index of diet overlap indicated seasonal variations in catfish diets with summer and monsoon displaying the least overlap, while maximum overlap during monsoon and winter seasons. The non-metric multidimensional scaling (nMDS) indicated the close association between the food items available during summer and winter seasons with a significant difference among the seasons (ANOSIM, R = 0.638, P = 0.013). Levin's niche breadth index arranged in the order of 0.88>0.81>0.78>0.63>0.43 for the size classes of V, IV, III, II and I, respectively. The PCA explained 95.39% of the total variance among the food items and fish size groups. Small-sized fish individuals displayed a greater correlation with food items suitable for their mouth size. In conclusion, the variety and frequency of food items recorded indicated considerable feeding plasticity and opportunistic feeding behavior with a shift from carnivorous to omnivorous feeding nature. This study could render useful information on the food and feeding habits of R. rita and provide background for preparing its diet for future aquaculture practices.

Ethnomedicinal uses, phytochemistry, and biological activities of plants of the genus Gynura

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Gynura (Compositae) includes around 46 species and is native to the tropical regions of Southeast Asia, Africa and Australia. Many species within this genus are used in ethnomedicine to treat various disorders including skin diseases, injuries, ulcers, wounds, burns, sores, scalds, as well as for the management of diabetes, hypertension, hyperlipidemia, constipation, rheumatism, bronchitis and inflammation.

AIM OF THE REVIEW

This review is an attempt to provide scientific information regarding the ethnopharmacology, phytochemistry, pharmacological and toxicological profiles of Gynura species along with the nomenclature, distribution, taxonomy and botanical features of the genus. A critical analysis has been undertaken to understand the current and future pharmaceutical prospects of the genus.

MATERIALS & METHODS

Several electronic databases, including Google scholar, PubMed, Web of Science, Scopus, ScienceDirect, SpringerLink, Semantic Scholar, MEDLINE and CNKI Scholar, were explored as information sources. The Plant List Index was used for taxonomical authentications. SciFinder and PubChem assisted in the verification of chemical structures.

RESULTS

A large number of phytochemical analyses on Gynura have revealed the presence of around 342 phytoconstituents including pyrrolizidine alkaloids, phenolic compounds, chromanones, phenylpropanoid glycosides, flavonoids, flavonoid glycosides, steroids, steroidal glycosides, cerebrosides, carotenoids, triterpenes, mono- and sesquiterpenes, norisoprenoids, oligosaccharides, polysaccharides and proteins. Several in vitro and in vivo studies have demonstrated the pharmacological potential of Gynura species, including antidiabetic, anti-oxidant, anti-inflammatory, antimicrobial, antihypertensive and anticancer activities. Although the presence of pyrrolizidine alkaloids within a few species has been associated with possible hepatotoxicity, most of the common species have a good safety profile.

CONCLUSIONS

The importance of the genus Gynura both as a prominent contributor in ethnomedicinal systems as well as a source of promising bioactive molecules is evident. Only about one fourth of Gynura species have been studied so far. This review aims to provide some scientific basis for future endeavors, including in-depth biological and chemical investigations into already studied species as well as other lesser known species of Gynura.

Leaf powder supplementation of Senna alexandrina ameliorates oxidative stress, inflammation, and hepatic steatosis in high-fat diet-fed obese rats

Obesity is an enduring medical issue that has raised concerns around the world. Natural plant extracts have shown therapeutic potential in preventing oxidative stress and inflammation related to obesity complications. In this study, Senna alexandrina Mill. leaves were utilized to treat high-fat diet-related metabolic disorders and non-alcoholic fatty liver diseases. Plasma biochemical assays were conducted to determine the lipid profiles and oxidative stress parameters, and the gene expression of antioxidant enzymes and inflammatory mediators was measured. Histological stained livers of high-fat diet-fed rats were observed. S. alexandrina leaf powder supplementation prevented the increase in cholesterol and triglyceride levels in high-fat diet-fed rats. Moreover, S. alexandrina leaves also reduced lipid peroxidation and nitric oxide production in these rats. Prevention of oxidative stress by S. alexandrina leaf supplementation in high-fat diet-fed rats is regulated by enhancing the antioxidant enzyme activity, followed by the restoration of corresponding gene expressions, such as NRF-2, HO-1, SOD, and CAT. Histological staining provides further evidence that S. alexandrina leaf supplementation prevents inflammatory cell infiltration, lipid droplet deposition, and fibrosis in the liver of high-fat diet-fed rats. Furthermore, this investigation revealed that S. alexandrina leaf supplementation controlled non-alcoholic fatty liver disease by modulating the expression of fat metabolizing enzymes in high-fat diet-fed rats. Therefore, S. alexandrina leaf supplementation inhibits fatty liver inflammation and fibrosis, suggesting its usefulness in treating non-alcoholic steatohepatitis. Thus, this natural leaf extract has potential in treatment of obesity related liver dysfunction.

Study on Alanine Aminotransferase in Patients of Type 2 Diabetes Mellitus

Type 2 Diabetes mellitus (DM) is associated with various types of liver disorders including elevated liver enzymes. This study was carried out to observe hepatocellular injury in type 2 Diabetes mellitus as evidenced by raised Alanine aminotransferase (ALT) among the type 2 Diabetes mellitus patients and to find out association between elevated ALT and glycaemic control. This was a descriptive cross-sectional comparative study carried out in Department of Medicine, Rajshahi Medical College Hospital and Rajshahi Diabetic Association Hospital, Rajshahi, Bangladesh from July 2009 to June 2010. One hundred (100) diagnosed type 2 diabetic patients according to WHO criteria and 30 apparently healthy people of both sexes were included. Age of the study people were >40 years. All of those study population were free from taking any hepatotoxic drugs, inj. Insulin, alcohol and preexisting liver disease. Detailed History, thorough clinical examination and relevant investigations were done for exclusion. The frequency of abnormal ALT, Serum bilirubin, Aspartate aminotransferase (AST), Alkaline phosphatase, Prothrombin time and Serum albumin were 30%, 6%, 7%, 6%, 54% and 12% respectively in type 2 diabetic patients and 3.3%, 00%, 00%, 6.7%, 10% and 3.3% respectively in normal people. Serum ALT (U/L) level (mean±SD) of the type 2 diabetic patients and normal people were (39.00±24.21) and (28.26±6.67) respectively. This difference is highly significant (p<0.001). Elevated serum ALT level of type 2 diabetic patients showed positive association with increased Body mass index (BMI) (p<0.05) and poor glycaemic control (p<0.05) and fatty liver (p=0.055). So, a high proportion of patients with type 2 diabetes mellitus have raised serum Alanine aminotransferase level. Elevated serum ALT level was also associated with high BMI, poor glycaemic control and fatty liver which may be a marker of NAFLD and insulin resistance.

Dietary polyphenols suppress chronic inflammation by modulation of multiple inflammation-associated cell signaling pathways

The high failure rate of the reductionist approach to discover effective and safe drugs to treat chronic inflammatory diseases has led scientists to seek alternative ways. Recently, targeting cell signaling pathways has been utilized as an innovative approach to discover drug leads from natural products. Cell signaling mechanisms have been identified playing key role in diverse diseases by inducing proliferation, cell survival and apoptosis. Phytochemicals are known to be able to modulate the cellular and molecular networks which are associated to chronic diseases including cancer-associated inflammation. In this review, the roles of dietary polyphenols (apigenin, kaempferol, quercetin, curcumin, genistein, isoliquiritigenin, resveratrol and gallic acid) in modulating multiple inflammation-associated cell signaling networks are deliberated. Scientific databases on suppressive effects of the polyphenols on chronic inflammation via modulation of the pathways especially in the recent five years are gathered and critically analyzed. The polyphenols are able to modulate several inflammation-associated cell signaling pathways, namely nuclear factor-kappa β, mitogen activated protein kinases, Wnt/β-catenin and phosphatidylinositol 3-kinase and protein kinase B via selective actions on various components of the networks. The suppressive effects of the polyphenols on the multiple cell signaling pathways reveal their potential use in prevention and treatment of chronic inflammatory disorders. Understanding the mechanistic effects involved in modulation of the signaling pathways by the polyphenols is necessary for lead identification and development of future functional foods for prevention and treatment of chronic inflammatory diseases.

Pharmacological insights on the antidepressant, anxiolytic and aphrodisiac potentials of Aglaonema hookerianum Schott

ETHNOPHARMACOLOGICAL RELEVANCE

Aglaonema hookerianum Schott is an ethnomedicinally important plant used to treat a variety of diseases, including sexual and depression-like disorders. However, the scientific basis underlying the aforesaid properties have not been well justified.

AIM OF THE STUDY

The present investigation aimed to investigate the anxiolytic, antidepressant and aphrodisiac potentials of methanol leaves extract of A. hookerianum (MEAH) in Swiss albino mice.

MATERIALS & METHODS

Swiss albino mice (20-30 g) were orally administrated with MEAH at the doses ranging from 100 to 400 mg/kg, b.w. The elevated plus maze (EPM) and hole board test (HBT) were performed to determine the anxiolytic activity and the forced swimming test (FST) and tail suspension test (TST) were performed to determine the antidepressant activity of MEAH. Besides, the aphrodisiac activity of MEAH was conducted through the mounting behaviour and orientation behaviour analysis. Diazepam (1 mg/kg, b.w., i.p.) for EPM and HBT; fluoxetine HCl (20 mg/kg, b.w., p.o.) for FST and TST, and sildenafil (5 mg/kg, b.w., p.o.) for the mounting behaviour analysis and orientation behaviour analysis were used as reference drugs.

RESULTS

The administration of the MEAH produced a strong (p < 0.001) dose-dependent anxiolytic effects in both HBT and EPM tests. Likewise, the extract revealed a significant (p < 0.001) reduction in the immobility time in both FST and TST as compared to the control group. Besides, the MEAH also found to possess marked aphrodisiac activity complying several facets such as an increase in the sexual performance at the highest dose (400 mg/kg, p.o.) as well as the orientation toward female mice (p < 0.001) at all tested doses.

CONCLUSION

Taken together, MEAH can be recommended as a potent source of neuroprotective and a libido-boosting drug candidate for the management of neurological and sexual disorders.

Polyphenol-rich leaf of Aphanamixis polystachya averts liver inflammation, fibrogenesis and oxidative stress in ovariectomized Long-Evans rats

Aphanamixis polystachya (Wall.) R.Parker, locally known as Pithraj, is a medicinal herb having enormous traditional applications. However, the scientific rationale underlying the ethnomedicinal claims was not well-founded. The current investigation aimed to explore the mechanistic insights of protective effects of ethanol extract of A. polystachya leaf (PT), given orally, on the chemical-intoxicated hepatic inflammation and fibrosis in Long-Evans female overiectomized rats. The GC-MS and HPLC-DAD analysis of PT revealed the presence of several bioactive metabolites, including polyphenolic compounds. Catechin hydrate, caffeic acid, syringic acid, epicatechin and p-coumaric acid have been identified and quantified in the ethanol extract of PT leaf. Intoxication with CCl₄ developed the oxidative stress, fibrosis and inflammation in liver of rats. Moreover, thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), advanced protein oxidation product (APOP) level were found increased; whereas superoxide dismutase (SOD) and catalase activities in the plasma and liver were decreased in CCl₄ administered rats. Treatment with PT prominently mitigated the oxidative stress (TBARS, NO, APOP), and inflammatory (MPO) markers and improved the endogenous antioxidant enzymes (catalase and SOD) activities in CCl₄-intoxicated rats. Additionally, histological assessment confirmed the clear manifestation of inflammation and fibrosis in the liver of CCl₄-intoxicated rats, which was prevented by PT and silymarin treatment. In conclusion, PT treatment may protect the liver in CCl₄-administered rats, probably by mitigating oxidative stress, inflammation and fibrosis, and also augmenting the function of the antioxidant enzymes.

Pretreatment of Blumea lacera leaves ameliorate acute ulcer and oxidative stress in ethanol-induced Long-Evan rat: A combined experimental and chemico-biological interaction

Blumea lacera (Burm.f.) DC. is described as a valuable medicinal plant in various popular systems of medicine. The aim of the experiment reports the in vivo antiulcer activity of methanol extract of Blumea lacera (MEBLL) and in silico studies of bioactive constituents of MEBLL. In this study, fasted Long-Evans rat treated with 80 % ethanol (0.5 mL) to induce gastric ulcer, were pretreated orally with MEBLL at different doses (250 and 500 mg/kg, p.o., b.w) and omeprazole (20 mg/kg, p.o.) and distilled water were used as a reference drug and normal control respectively. In silico activity against gastric H+-K+ATPase enzyme was also studied. The findings demonstrated that the treatment with MEBLL attenuated markedly ulcer and protected the integrity of the gastric mucosa by preventing the mucosal ulceration altered biochemical parameters of gastric juice such total carbohydrate, total protein and pepsin activity. Additionally, the experimental groups significantly (p < 0.001) inhibited gastric lesions and malondealdehyde (MDA) levels and upregulated antioxidant enzymes level. Furthermore, nine compounds were documented as bioactive, displayed good binding affinities to against gastric H+-K+ATPase enzyme while these compounds illustrated inhibitory effect. From these studies, it is established MEBLL has ulcer healing property as unveiled by in vivo and in silico studies.

Stem extract of Albizia richardiana exhibits potent antioxidant, cytotoxic, antimicrobial, anti-inflammatory and thrombolytic effects through in vitro approach

Background

Albizia richardiana belongs Fabaceae family which different parts like fruits, flowers, barks, and roots are used medicinally. The study reports the in vitro anti-inflammatory, thrombolytic, cytotoxicity and antimicrobial activity of methanolic extract of A. richardiana stem and its different fractions.

Method

The methanolic extract of A. richardiana stem (MEAR) extracted with n-hexane (HXFAR), carbon tetrachloride (CTFAR), chloroform (CFAR), and aqueous (AQFAR) and subjected for DPPH scavenging activity and total phenol content (TPC). The cytotoxic activity evaluated by brine shrimp lethality bioassay, while the disk diffusion method used for the antimicrobial study. The anti-inflammatory and thrombolytic activities of the extracts evaluated by the hypotonic solution induced hemolysis, heat-induced hemolysis and human blood clot lysis, respectively.

Results

All the extracts exhibited excellent antioxidant activity in the DPPH scavenging assay and maximum total phenol content observed by HXFAR. Secondly, the extract showed a moderate LC50 value in brine shrimp lethality bioassay, where the CTFAR extract exhibited potential antimicrobial activities against sixteen different microorganisms. In anti-inflammatory, all the extract exhibited a significant (P < 0.0001) protection against lysis of human erythrocyte membrane induced by heat and hypotonic solution, as compared to the standard acetyl salicylic acid. An extremely significant (P < 0.0001) clot lysis was found in MEAR (16.66%) while the standard drug streptokinase (70.94%).

Conclusion

All the fractions revealed the significant free radical scavenging activity. Moreover, CTFAR showed wide spectrum of antimicrobial activity. Thus, the results of the present study provided scientific evidence for the use of Albizia richardiana as traditional medicine.

Pharmacological insights and prediction of lead bioactive isolates of Dita bark through experimental and computer-aided mechanism

Dita bark (Alstonia scholaris (L.) R. Br.) is an ethnomedicine used for the management of various ailments. This study aimed to investigate the biological properties of methanol extract of A. scholaris bark (MEAS), through in vivo, in vitro and in silico approaches alongside its phytochemical profiling. Identification and nature of the bioactive secondary metabolites were studied by the established qualitative tests and GC-MS analysis. The antidepressant activity was determined by forced swimming test (FST) and tail suspension test (TST) in mice. The anti-inflammatory and thrombolytic effect was evaluated using inhibition of protein denaturation technique and clot lysis technique, respectively. Besides, computational studies of the isolated compounds and ADME/T analysis were performed by Schrödinger-Maestro (v11.1) software, and PASS prediction was conducted through PASS online tools. The GC-MS analysis revealed the presence of several secondary metabolites in MEAS. Treatment with MEAS revealed a significant reduction of immobility time in a dose-dependent manner in FST and TST. Besides, MEAS showed substantial anti-inflammatory effects at the higher dose (400 μg/mL) as well as revealed notable clot lysis effect as compared to control. In the case of computer-aided investigation, all compounds meet the condition of Lipinski's rule of five. PASS study also predicted for all compounds, and among these safe compound furazan-3-amine showed the most spontaneous binding energy for both antidepressant and thrombolytic activities, as well as 5-dimethylamino-6 azauracil, found promising for anti-inflammatory activity. Taken together, the investigation concludes that MEAS can be a potent source of antidepressant, anti-inflammatory, and thrombolytic agents.

Standardized ethanol extract of Tinospora crispa upregulates pro-inflammatory mediators release in LPS-primed U937 human macrophages through stimulation of MAPK, NF-κB and PI3K-Akt signaling networks

BACKGROUND

Immunomodulatory effects of Tinospora crispa have been investigated due to its traditional use to treat several inflammatory disorders associated to the immune system. The present study reports the underlying mechanisms involved in the stimulation of 80% ethanol extract of T. crispa stems on pro-inflammatory mediators release in lipopolysaccharide (LPS)-primed U937 human macrophages via MyD88-dependent pathways.

METHODS

Release of interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and production of prostaglandin E₂ (PGE₂) were determined by using enzyme-linked immunosorbent assay (ELISA). Immunoblot technique was executed to determine the activation of MAPKs molecules, NF-κB, PI3K-Akt and cyclooxygenase-2 (COX-2) protein. Determination of pro-inflammatory cytokines and COX-2 relative gene expression levels was by performing the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). A reversed-phase HPLC method was developed and validated to standardize the T. crispa extract and chemical profiling of its secondary metabolites was performed by LC-MS/MS.

RESULTS

Qualitative and quantitative analyses of chromatographic data indicated that syringin and magnoflorine were found as the major components of the extract. T. crispa-treatment prompted activation of NF-κB by enhancing IKKα/β and NF-κB (p65) phosphorylation, and degradation of IκBα. The extract upregulated COX-2 protein expression, release of pro-inflammatory mediators and MAPKs (ERK, p38 and JNK) phosphorylation as well as Akt dose-dependently. T. crispa extract also upregulated the upstream signaling adaptor molecules, toll-like receptor 4 (TLR4) and MyD88. T. crispa-treatment also upregulated the pro-inflammatory markers mRNA expression.

CONCLUSION

The results suggested that T. crispa extract stimulated the MyD88-dependent signaling pathways by upregulating the various immune inflammatory related parameters.

Polyphenolic compounds of amla prevent oxidative stress and fibrosis in the kidney and heart of 2K1C rats

Amla (Emblica officinalis Gaertn.) is a natural source of antioxidants and possesses valuable medicinal properties. However, the protective effect of amla in the kidney of two-kidneys-one-clip (2K1C) rats has not been explained sufficiently. This study was performed to evaluate the renoprotective effect of amla fruit powder (2.5% W/W) supplementation in kidneys of 2K1C rats. 2K1C rats increased the remnant kidney wet weight and also increased plasma creatinine and uric acid concentration compared to the control. Amla supplementation ameliorates elevated creatinine and uric acid concentration in plasma of 2K1C rats. Various oxidative stress indicators such as malondialdehyde, nitric oxide (NO), and advanced protein oxidation product (APOP) were also increased in plasma, heart, and kidney tissues in 2K1C rats that were also significantly brought down to normal level by amla supplementation. Moreover, the inflammatory cells entry and fibrosis in the 2K1C rat's tissues were prevented by amla supplementation. These research results suggest that amla may restore plasma antioxidant capacities and prevents oxidative stress, inflammation, and fibrosis in 2K1C rats. Taken these results as a base, clinical supplementation of dried amla powder in diet or juice to the CKD patients would be beneficial.

Curculigo recurvata W.T.Aiton exhibits anti-nociceptive and anti-diarrheal effects in Albino mice and an in silico model

BACKGROUND

Curculigo recurvata (C. recurvata) is an enthnomedicinally important herb reported to have significant medicinal values. The present study aimed to explore the in vivo and in silico anti-nociceptive and anti-diarrheal effects of a C. recurvate rhizome methanol extract (Me-RCR).

METHODS

The analgesic effects of Me-RCR were assessed using acetic acid-induced writhing and the formalin-induced flicking test. The drugs were administered intraperitoneally (IP) at doses of 200 and 400 mg/kg body weight (bw). Anti-diarrheal activity was evaluated by assessing intestinal motility, hypersecretion, and fecal score in mice at oral doses of 200 and 400 mg/kg·bw. Computer facilitated analyses for anti-nociceptive and anti-diarrheal activities of three isolated compounds from C. recurvata were undertaken to identify the best-fit phytoconstituents.

RESULTS

The Me-RCR showed significant (P < .05) peripheral anti-nociception at the highest dose. The extract inhibited both early and late phases of nociception in the formalin-induced writhing test. In the castor oil-induced diarrhoea model, the extract significantly (P < .05) prolonged the onset time of diarrhoea, inhibited percentage of diarrhoea, and decreased both the volume and weight of intestinal contents. Rates of intestinal fluid accumulation inhibition were (33.61 ± 1.00)% and (46.44 ± 0.89)% at Me-RCR doses of 200 and 400 mg/kg·bw, respectively. Moreover, a significant (P < .05) reduction in gastrointestinal motility was observed. An absorption, distribution, metabolism, excretion and/or toxicity (ADME/T) test showed that the selected compounds yielded promising results, satisfying Lipinski's rule of five for predicting drug-like potential. Notably, of the three phytoconstituents curculigine and isocurculigine possessed the highest affinity for the COX-1 and COX-2. Isocurculigine was also identified as the most effective anti-diarrheal compound in the computer-facilitated model.

CONCLUSION

An extract of the plant C. recurvata showed potential analgesic and anti-diarrheal activity due to the presence of one or more active secondary metabolite(s).

Supplements of an aqueous combination of Justicia adhatoda and Ocimum tenuiflorum boost antioxidative effects and impede hyperlipidemia

BACKGROUND

Justicia adhatoda and Ocimum tenuiflorum, locally known as bashok and tulsi, are two ethnomedicinally important herbs that have been using as dietary supplements for several therapeutic applications. This study evaluated the combined effect of both the herbs as an antioxidative and antihyperlipidemic agent.

METHODS

Antihyperlipidemic effect was assessed in a high-fat diet-induced hyperlipidemic model in Wistar albino rats. The rats were treated orally with extracts of bashok (J adhatoda, 200 mg/kg bw), tulshi (O tenuiflorum, 200 mg/kg bw), and a combination of bashok and tulshi (50:50), as well as with a reference drug, atorvastatin (10 mg/kg/day), with or without high-fat diet for 14 days. The antioxidative effect was studied using established in vitro models. The studies were supported by experimentally testing the effects of the extracts on membrane stabilization and inhibition of protein denaturation.

RESULTS

The results showed that the serum lipid profile was significantly decreased in the different treatment groups, with bashok having the greatest effect. Body weights, total serum protein, LDH, and relative liver and adipose tissue weights were markedly restored towards baseline values, the lowest atherogenic index being achieved with the combined extract. The combination treatment significantly enhanced total phenolic content and antioxidative capacity and greatly potentiated membrane stabilization, but inhibition of protein denaturation was not significantly affected.

CONCLUSION

The data demonstrate that a combination of Justicia adhatoda and Ocimum tenuiflorum could be developed as a food supplement with antioxidative and antihyperlipidemic benefits.

Modulation of cell signaling pathways by Phyllanthus amarus and its major constituents: potential role in the prevention and treatment of inflammation and cancer

The causal and functional connection between inflammation and cancer has become a subject of much research interest. Modulation of cell signaling pathways, such as those involving mitogen activated protein kinases (MAPKs), nuclear factor kappa β (NF-κB), phosphatidylinositol 3-kinase and protein kinase B (PI3K/Akt), and Wnt, and their outcomes play a fundamental role in inflammation and cancer. Activation of these cell signaling pathways can lead to various aspects of cancer-related inflammation. Hence, compounds able to modulate inflammation-related molecular targets are sought after in anticancer drug development programs. In recent years, plant extracts and their metabolites have been documented with potential in the prevention and treatment of cancer and inflammatory ailments. Plants possessing anticancer and anti-inflammatory properties due to their bioactive constituents have been reported to modulate the molecular and cellular pathways which are related to inflammation and cancer. In this review we focus on the flavonoids (astragalin, kaempferol, quercetin, rutin), lignans (phyllanthin, hypophyllanthin, and niranthin), tannins (corilagin, geraniin, ellagic acid, gallic acid), and triterpenes (lupeol, oleanolic acid, ursolic acid) of Phyllanthus amarus, which exert various anticancer and anti-inflammatory activities via perturbation of the NF-κB, MAPKs, PI3K/Akt, and Wnt signaling networks. Understanding the underlying mechanisms involved may help future research to develop drug candidates for prevention and new treatment for cancer and inflammatory diseases.

Standardized ethanol extract, essential oil and zerumbone of Zingiber zerumbet rhizome suppress phagocytic activity of human neutrophils

BACKGROUND

Zingiber zerumbet rhizome and its bioactive metabolites have previously been reported to exhibit innumerable pharmacological properties particularly anti-inflammatory activities. In the present study, the 80% ethanol extract, essential oil and zerumbone of Z. zerumbet rhizomes were explored for their in vitro immunosuppressive properties on chemotaxis, CD11b/CD18 expression, phagocytosis and chemiluminescence of isolated human polymorphonuclear neutrophils (PMNs).

METHODS

The extract was analyzed quantitatively by performing a validated reversed phase high performance liquid chromatography (RP-HPLC). Zerumbone was isolated by chromatographic technique while the essential oil was acquired through hydro-distillation of the rhizomes and further analyzed by gas chromatography (GC) and GC-MS. Chemotaxis assay was assessed by using a 24-well cell migration assay kit, while CD18 integrin expression and phagocytic engulfment were measured using flow cytometry. The reactive oxygen species (ROS) production was evaluated by applying lucigenin- and luminol-enhanced chemiluminescence assays.

RESULTS

Zerumbone was found to be the most abundant compound in the extract (242.73 mg/g) and the oil (58.44%). Among the samples tested, the oil revealed the highest inhibition on cell migration with an IC50 value of 3.24 μg/mL. The extract, oil and zerumbone showed moderate inhibition of CD18 integrin expression in a dose-dependent trend. Z. zerumbet extract showed the highest inhibitory effect on phagocytic engulfment with percentage of phagocytizing cells of 55.43% for PMN. Zerumbone exhibited strong inhibitory activity on oxidative burst of zymosan- and PMA-stimulated neutrophils. Zerumbone remarkably inhibited extracellular ROS production in PMNs with an IC50 value of 17.36 μM which was comparable to that of aspirin.

CONCLUSION

The strong inhibition on the phagocytosis of neutrophils by Z. zerumbet extract and its essential oil might be due the presence of its chemical components particularly zerumbone which was capable of impeding phagocytosis at different stages.

An Insight Into the Modulatory Effects and Mechanisms of Action of Phyllanthus Species and Their Bioactive Metabolites on the Immune System

Phyllanthus species (family; Euphorbiaceae) have been intensively studied for their immunomodulating effects due to their wide-ranging uses to treat immune-related diseases in indigenous medicine, which are primarily lack of scientific basis. The focuses of this review are on the significance of Phyllanthus species and their bioactive metabolites particularly corilagin (1), geraniin (2), gallic acid (3), phyllanthin (4), hypophyllanthin (5), ellagic acid (6), phyltetralin (7), niranthin (8), catechin (9), quercetin (10), astragalin (11), and chebulagic acid (12) in the modulation of both innate and adaptive immune systems through various mechanisms and their possible therapeutic benefits for treatment of immune-related diseases. We have compiled all significant findings published in the literature, and the data were analyzed critically to provide perspectives and directions for future research for the plants as a prospective source of novel immunomodulating agents. Various Phyllanthus species particularly Phyllanthus amarus, Phyllanthus emblica, Phyllanthus niruri, and Phyllanthus urinaria have been documented to possess significant immunomodulatory effects. However, the possible challenges encountered by the application of extracts of various Phyllanthus species and their bioactive constituents as immunomodulators need to be addressed. Most reports on the biological and pharmacological studies of the plants were based on crude extracts. The extracts were not chemically characterized, and the contributions of their chemical constituents to the bioactivities were not identified. The underlying mechanisms involved in the immunomodulatory effects of the Phyllanthus species were not indepthly studied due to limitations in terms of design, conduct, and interpretation. Extensive experimental and preclinical studies on the immunomodulating potential of Phyllanthus species should be carried out to provide sufficient data to prove that their traditional uses are inherently effective and safe and will allow clinical trials to be pursued for their further development as therapeutic agents to treat immune-related disorders.

Zerumbone from Zingiber zerumbet inhibits innate and adaptive immune responses in Balb/C mice

Zerumbone exhibited various biological properties including in vitro immunosuppressive effects. However, its modulatory activity on the immune responses in experimental animal model is largely unknown. This investigation was conducted to explore the effects of daily treatment of zerumbone (25, 50, and 100 mg/kg) isolated from Zingiber zerumbet rhizomes for 14 days on various cellular and humoral immune responses in Balb/C mice. For measurement of adaptive immunity, sheep red blood cells (sRBC) were used to immunize the mice on day 0 and orally fed with similar doses of zerumbone for 14 days. The effects of zerumbone on phagocytosis, nitric oxide (NO) release, myeloperoxidase (MPO) activity, proliferation of T and B cells, lymphocyte phenotyping, cytokines release in serum by activated T cells, delayed type hypersensitivity (DTH) and immunoglobulins production (IgG and IgM) were investigated. Zerumbone downregulated the engulfment of E. coli by peritoneal macrophages and the release of NO and MPO in a concentration-dependent manner. Zerumbone showed significant and concentration-dependent suppression of T and B lymphocytes proliferation and inhibition of the Th1 and Th2 cytokines release. At higher concentrations of zerumbone, the % expression of CD4⁺ and CD8⁺ in splenocytes was significantly inhibited. Zerumbone also concentration-dependently demonstrated strong suppression on sRBC-triggered swelling of mice paw in DTH. Substantial suppression of anti-sRBC immunoglobulins antibody titer was noted in immunized and zerumbone-treated mice in a concentration-dependent manner. The potent suppressive effects of zerumbone on the immune responses suggest that zerumbone can be a potential candidate for development of immunosuppressive agent.

Standardized extract of Zingiber zerumbet suppresses LPS-induced pro-inflammatory responses through NF-κB, MAPK and PI3K-Akt signaling pathways in U937 macrophages

BACKGROUND

Zingiber zerumbet rhizome has been used as spices and in traditional medicine to heal various immune-inflammatory related ailments. Although the plant was reported to have potent anti-inflammatory and immunosuppressive properties by several studies, the molecular mechanisms underlying the effects have not been well justified.

PURPOSE

The study was carried out to investigate the molecular mechanisms underlying the anti-inflammatory properties of the standardized 80% ethanol extract of Z. zerumbet through its effect on mitogen-activated protein kinase (MyD88)-dependent nuclear factor-kappa B (NF-кB), mitogen activated protein kinase (MAPK) and phosphatidylinositol 3-kinase/Akt (PI3K-Akt) signaling pathways in lipopolysaccharide (LPS)-induced U937 human macrophages.

METHODS

Standardization of the 80% ethanol extract of Z. zerumbet was performed by using a validated reversed-phase HPLC method, while LC-MS/MS was used to profile the secondary metabolites. The release of pro-inflammatory markers, tumor necrosis factor (TNF)-α, interleukin (IL)-1β and prostaglandin E₂ (PGE₂) was evaluated by enzyme-linked immunosorbent assay (ELISA), while the Western blot technique was executed to elucidate the expression of mediators linked to MyD88-dependent respective signaling pathways. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay was carried out to quantify the relative gene expression of cyclooxygenase (COX)-2 and pro-inflammatory mediators at the transcriptional level.

RESULTS

The quantitative and qualitative analyses of Z. zerumbet extract showed the presence of several compounds including the major chemical marker zerumbone. Z. zerumbet extract suppressed the release of pro-inflammatory mediators, COX-2 protein expression and downregulated the mRNA expression of pro-inflammatory markers. Z. zerumbet-treatment also blocked NF-κB activation by preventing the phosphorylation of IKKα/β and NF-κB (p65) as well as the phosphorylation and degradation of IκBα. Z. zerumbet extract concentration-dependently inhibited the phosphorylation of respective MAPKs (JNK, ERK, and p38) as well as Akt. Correspondingly, Z. zerumbet extract suppressed the upstream signaling adaptor molecules, TLR4 and MyD88 prerequisite for the NF-κB, MAPKs, and PI3K-Akt activation.

CONCLUSION

The findings suggest that Z. zerumbet has impressive role in suppressing inflammation and related immune disorders by inhibition of various pro-inflammatory markers through the imperative MyD88-dependent NF-κB, MAPKs, and PI3K-Akt activation.

Immunosuppressive effects of the standardized extract of Zingiber zerumbet on innate immune responses in Wistar rats

Zingiber zerumbet rhizome has been used in traditional medicine mainly for the treatment of various immune-inflammatory related ailments and has been shown to exhibit a wide spectrum of biological effects especially antioxidant and anti-inflammatory activities. The present study was aimed to investigate the immunosuppressive effects of the standardized 80% ethanol extract of Z. zerumbet at 100, 200, and 400 mg/kg on the innate immune responses in male Wistar rats. The immune parameters determined were chemotaxis of neutrophils, Mac-1 expression, engulfment of Escherichia coli by neutrophils, reactive oxygen species production, and plasma lysozyme and ceruloplasmin levels. Zerumbone was qualitatively and quantitatively determined in the extract by using a validated reversed-phase HPLC, whereas liquid chromatography tandem-mass spectrometry (LC -MS/MS) was used to profile the secondary metabolites. Z. zerumbet significantly inhibited the migration of neutrophils, expressions of CD11b/CD18 integrin, phagocytic activity, and production of reactive oxygen species in a dose-dependent manner. The extract also dose-dependently inhibited the expressions of lysozyme and ceruloplasmin in the rat plasma. Z. zerumbet extract possessed strong inhibitory effects on the innate immune responses and has potential to be developed into an effective immunosuppressive agent.

Magnoflorine Enhances LPS-Activated Pro-Inflammatory Responses via MyD88-Dependent Pathways in U937 Macrophages

Magnoflorine, a major bioactive metabolite isolated from Tinospora crispa, has been reported for its diverse biochemical and pharmacological properties. However, there is little report on its underlying mechanisms of action on immune responses, particularly on macrophage activation. In this study, we aimed to investigate the effects of magnoflorine, isolated from T. crispa on the pro-inflammatory mediators generation induced by LPS and the concomitant NF-κB, MAPKs, and PI3K-Akt signaling pathways in U937 macrophages. Differentiated U937 macrophages were treated with magnoflorine and the release of pro-inflammatory mediators was evaluated through ELISA, while the relative mRNA expression of the respective mediators was quantified through qRT-PCR. Correspondingly, western blotting was executed to observe the modulatory effects of magnoflorine on the expression of various markers related to NF-κB, MAPK and PI3K-Akt signaling activation in LPS-primed U937 macrophages. Magnoflorine significantly enhanced the upregulation of TNF-α, IL-1β, and PGE₂ production as well as COX-2 protein expression. Successively, magnoflorine prompted the mRNA transcription level of these pro-inflammatory mediators. Magnoflorine enhanced the NF-κB activation by prompting p65, IκBα, and IKKα/β phosphorylation as well as IκBα degradation. Besides, magnoflorine treatments concentration-dependently augmented the phosphorylation of JNK, ERK, and p38 MAPKs as well as Akt. The immunoaugmenting effects were further confirmed by investigating the effects of magnoflorine on specific inhibitors, where the treatment with specific inhibitors of NF-κB, MAPKs, and PI3K-Akt proficiently blocked the magnoflorine-triggered TNF-α release and COX-2 expression. Magnoflorine furthermore enhanced the MyD88 and TLR4 upregulation. The results suggest that magnoflorine has high potential on augmenting immune responses.

Anti-Inflammatory Effects of Hypophyllanthin and Niranthin Through Downregulation of NF-κB/MAPKs/PI3K-Akt Signaling Pathways

Hypophyllanthin (HYP) and niranthin (NIR) are major lignans in Phyllanthus spp. and have been shown to possess strong anti-inflammatory activity. In this study, we investigated the anti-inflammatory effects and the underlying molecular mechanisms of HYP and NIR in in vitro cellular model of LPS-induced U937 macrophages. The effects of HYP and NIR on the production of prostaglandin E₂ (PGE₂), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) were measured by using ELISA, Western blot, and qRT-PCR. The expressions of signaling molecules related to nuclear factor-kappa B (NF-κB), mitogen-activated protein kinases (MAPKs), and phosphatidylinositol 3'-kinase-Akt (PI3K-Akt) signaling pathways were examined. The role of NF-κB, MAPKs, and Akt signaling pathways was confirmed by using specific inhibitors (BAY 11-7082, U0126, SB202190, SP600125, and LY294002) mediated suppression of TNF-α and COX-2 production. HYP and NIR significantly inhibited the protein and gene levels of COX-2 as well as the downstream signaling products of PGE₂, TNF-α, and IL-1β. HYP and NIR also suppressed the inhibitors of kappa B (IκB), IkB kinases (Ikkα/β), NF-κB phosphorylation, and IκB degradation. HYP suppressed the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 while NIR only suppressed JNK and ERK but did not have effect on p38. These results demonstrate that HYP and NIR downregulated COX-2, TNF-α, and IL-1β gene expressions in U937 macrophages by interfering with the activation of NF-κB, MAPKs, and Akt. In conclusion, these lignans have potential to be developed as anti-inflammatory agents targeting the NF-κB, MAPK, and PI3K-Akt pathways.

Anti-inflammatory effects of Phyllanthus amarus Schum. & Thonn. through inhibition of NF-κB, MAPK, and PI3K-Akt signaling pathways in LPS-induced human macrophages

Background

Phyllanthus amarus has been used widely in various traditional medicines to treat swelling, sores, jaundice, inflammatory diseases, kidney disorders, diabetes and viral hepatitis, while its pharmacological and biochemical mechanisms underlying its anti-inflammatory properties have not been well investigated. The present study was carried out to investigate the effects of 80% ethanolic extract of P. amarus on pro-inflammatory mediators release in nuclear factor-kappa B (NF-кB), mitogen activated protein kinase (MAPK) and phosphatidylinositol 3-kinase/Akt (PI3K-Akt) signaling activation in lipopolysaccharide (LPS)-induced U937 human macrophages.

Methods

The release of prostaglandin E₂ (PGE₂) and pro-inflammatory cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β in a culture supernatant was determined by ELISA. Determination of cyclooxygenase-2 (COX-2) protein and the activation of MAPKs molecules (JNK, ERK and p38 MAPK), NF-κB and Akt in LPS-induced U937 human macrophages were investigated by immunoblot technique. The relative gene expression levels of COX-2 and pro-inflammatory cytokines were measured by using qRT-PCR. The major metabolites of P. amarus were qualitatively and quantitatively analyzed in the extract by using validated reversed-phase high performance liquid chromatography (HPLC) methods.

Results

P. amarus extract significantly inhibited the production of pro-inflammatory mediators (TNF-α, IL-1β, PGE₂) and COX-2 protein expression in LPS-induced U937 human macrophages. P. amarus-pretreatment also significantly downregulated the increased mRNA transcription of pro-inflammatory markers (TNF-α, IL-1β, and COX-2) in respective LPS-induced U937 macrophages. It downregulated the phosphorylation of NF-κB (p65), IκBα, and IKKα/β and restored the degradation of IκBα, and attenuated the expression of Akt, JNK, ERK, and p38 MAPKs phosphorylation in a dose-dependent manner. P. amarus extract also downregulated the expression of upstream signaling molecules, TLR4 and MyD88, which play major role in activation of NF-κB, MAPK and PI3K-Akt signaling pathways. The quantitative amounts of lignans, phyllanthin, hypophyllahtin and niranthin, and polyphenols, gallic acid, geraniin, corilagin, and ellagic acid in the extract were determined by HPLC analysis.

Conclusion

The study revealed that P. amarus targeted the NF-κB, MAPK and PI3K-Akt signaling pathways to exert its anti- inflammatory effects by downregulating the prospective inflammatory signaling mediators.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2289-3) contains supplementary material, which is available to authorized users.

Metal-Adapted Bacteria Isolated From Wastewaters Produce Biofilms by Expressing Proteinaceous Curli Fimbriae and Cellulose Nanofibers

Bacterial biofilm plays a pivotal role in bioremediation of heavy metals from wastewaters. In this study, we isolated and identified different biofilm producing bacteria from wastewaters. We also characterized the biofilm matrix [i.e., extracellular polymeric substances (EPS)] produced by different bacteria. Out of 40 isolates from different wastewaters, only 11 (27.5%) isolates (static condition at 28°C) and 9 (22.5%) isolates (agitate and static conditions at 28 and 37°C) produced air–liquid (AL) and solid–air–liquid (SAL) biofilms, respectively, only on salt-optimized broth plus 2% glycerol (SOBG) but not in other media tested. Biomass biofilms and bacteria coupled with AL biofilms were significantly (P ≤ 0.001) varied in these isolates. Escherichia coli (isolate ENSD101 and ENST501), Enterobacter asburiae (ENSD102), Enterobacter ludwigii (ENSH201), Pseudomonas fluorescens (ENSH202 and ENSG304), uncultured Vitreoscilla sp. (ENSG301 and ENSG305), Acinetobacter lwoffii (ENSG302), Klebsiella pneumoniae (ENSG303), and Bacillus thuringiensis (ENSW401) were identified based on 16S rRNA gene sequencing. Scanning electron microscope (SEM) images revealed that biofilm matrix produced by E. asburiae ENSD102, uncultured Vitreoscilla sp. ENSG301, A. lwoffii ENSG302, and K. pneumoniae ENSG303 are highly fibrous, compact, and nicely interlinked as compared to the biofilm developed by E. ludwigii ENSH201 and B. thuringiensis ENSW401. X-ray diffraction (XRD) results indicated that biofilm matrix produced by E. asburiae ENSD102, uncultured Vitreoscilla sp. ENSG301, and A. lwoffii ENSG302 are non-crystalline amorphous nature. Fourier transform infrared (FTIR) spectroscopy showed that proteins and polysaccharides are the main components of the biofilms. Congo red binding results suggested that all these bacteria produced proteinaceous curli fimbriae and cellulose-rich polysaccharide. Production of cellulose was also confirmed by Calcofluor binding- and spectrophotometric assays. E. asburiae ENSD102, Vitreoscilla sp. ENSG301, and A. lwoffii ENSG302 were tested for their abilities to form the biofilms exposure to 0 to 2000 mg/L of copper sulfate (for Cu), zinc sulfate (for Zn), lead nitrate (for Pb), nickel chloride (for Ni), and potassium dichromate (for Cr), several concentrations of these metals activated the biofilm formation. The polysaccharides is known to sequester the heavy metals thus, these bacteria might be applied to remove the heavy metals from wastewater.