Experimental antibacterial activity of selective cyclooxygenase antagonist

Background: From the history of the development of pharmaceutical compounds it is evident that any drug may have the possibility of possessing diverse functions and thus may have useful activity in completely different fields of medicine and different studies showed that newer antimicrobials have revealed antimicrobial action involved in the management of diseases of non-infectious etiology. This study was done to determine in vitro antibacterial activity of selected selective cyclooxygenase-2 inhibitor.Methods: Twenty two strains of gram positive and gram negative bacteria, which were isolated from skin and urinary tract infected patient. These bacteria were being cultured on specific optimal growth media. The antibacterial activity of selective COX-2 (meloxicam, celecoxib, valdecoxib and nimesulide). Inhibitors determined by measuring zone of inhibition and minimal inhibitory concentration (MIC).Results: Results showed that MIC of celecoxib and meloxicam in µg/ml was ranged from 5-80µg/ml on selected bacteria compared with negative control distilled water (D.W) ,valdecoxib was 80-160µg/ml, while and nimesulide was ranged from 5-40 µg/ml .All the selected bacteria were showed sensitivity for all coxib used in this experimental study except Pseudomonas aeruginosa which showed resistant to meloxicam and valdecoxib, Klebsiella pneumoniae resist to nimesulide while Staphylococcus aureus was resist to valdecoxib. The smaller zone of inhibition showed by valdecoxib and celecoxib which was 3mm against Klebsiella pneumoniae, while the larger zone of inhibition showed by nimesulide which was 26mm against Escherichia coli.Conclusions: In conclusion selective cyclooxygenase (cox-2) inhibitor possesses antibacterial activity this is especially for nimesulide and little by valdecoxib. Escherichia coli are sensitive bacteria to all coxib. Consequently; coxib may be regarded as anti-inflammatory and antibacterial agent especially for urinary tract infection where Escherichia coli are the major causative organism

The Potential Role of Renin Angiotensin System (RAS) and Dipeptidyl Peptidase-4 (DPP-4) in COVID-19: Navigating the Uncharted

Novel coronavirus (COVID-19) led to infected pneumonia and acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI). The entry-point receptor for COVID-19 is angiotensin-converting enzyme 2 (ACE2) at lung, and dipeptidyl peptidase-4 (DPP-4) is a receptor for Middle East respiratory syndrome coronavirus (MERS-CoV). There is 80% similarity between MERS-CoV and COVID-19. This study was planned to review the potential link between the incidence and severity of COVID-19 regarding the modulation of DPP-4 and ACE2 by DPP-4 and renin angiotensin system (RAS). In COVID-19, SARS-CoV2 binds ACE2 which is highly expressed by the epithelial cells of the blood vessel, intestine, and lung. However, pulmonary ACE2 seems to be a protective defense pathway during ARDS. DPP-4 is not concerned with the entry of COVID-19 but mediates the inflammatory reactions and cytokine storm that induced ARDS and AKI by COVID-19. The interaction between DPP4i and RAS inhibitors seem to augment the expression of AT2 receptor and ACE2 which are under extensive researches to find the pathophysiological pathway of COVID-19 infection. This beneficial interaction between DPP4i and RAS shed light for possible attenuation of COVID-19-induced ARDS and AKI mainly in critically ill patients with systemic hypertension

Activation of TORC1 transcriptional coactivator through MEKK1-induced phosphorylation

CREB is a prototypic bZIP transcription factor and a master regulator of glucose metabolism, synaptic plasticity, cell growth, apoptosis, and tumorigenesis. Transducers of regulated CREB activity (TORCs) are essential transcriptional coactivators of CREB and an important point of regulation on which various signals converge. In this study, we report on the activation of TORC1 through MEKK1-mediated phosphorylation. MEKK1 potently activated TORC1, and this activation was independent of downstream effectors MEK1/MEK2, ERK2, JNK, p38, protein kinase A, and calcineurin. MEKK1 induced phosphorylation of TORC1 both in vivo and in vitro. Expression of the catalytic domain of MEKK1 alone in cultured mammalian cells sufficiently caused phosphorylation and subsequent activation of TORC1. MEKK1 physically interacted with TORC1 and stimulated its nuclear translocation. An activation domain responsive to MEKK1 stimulation was mapped to amino acids 431-650 of TORC1. As a physiological activator of CREB, interleukin 1α triggered MEKK1-dependent phosphorylation of TORC1 and its consequent recruitment to the cAMP response elements in the interleukin 8 promoter. Taken together, our findings suggest a new mechanism for regulated activation of TORC1 transcriptional coactivator and CREB signaling. © 2008 by The American Society for Cell Biology.published_or_final_versio

Levothyroxine improves Paraoxonase (PON-1) serum levels in patients with primary hypothyroidism: Case–control study

Primary hypothyroidism is associated with oxidative stress and insufficient antioxidant capacity. This study was conducted to evaluate the effects of levothyroxine replacement therapy on paraoxonase 1 (PON-1) serum levels in a patients with primary hypothyroidism. Thirty-one patients with primary hypothyroidism compared to 20 healthy controls were recruited from. A venous blood sample were taken after an overnight fasting for biochemical parameters, before and after starting levothyroxine therapy (100 μ g/day) for 3 months duration. The biochemical variables were PON-1 serum levels, lipid profiles, triiodothyronine (T3), thyroxin (T4), and thyroid stimulating hormone (TSH) serum levels. Levothyroxine replacement therapy leads to a significant amelioration of thyroid functions, lipid profile, cardiometabolic measures P < 0.05 in patients with primary hypothyroidism. Levothyroxine leads to significant elevation in PON-1 serum levels from 188.42 ± 19.81 (U/mL) to 361.23 ± 33.62 (U/mL) P < 0.0001. This study concluded that levothyroxine replacement therapy significantly increases PON-1 serum levels in patients with primary hypothyroidism and attenuating hypothyroidism-induced oxidative stress

Sulfonylurea and neuroprotection: The bright side of the moon

Sulfonylurea (SUR) agents are the second and most used oral hypoglycemic drugs after metformin and they still as an imperative tool for most favorable of glucose control. SURs are used mainly in the management of Type 2 diabetes mellitus since; they are effective in the glycemic control and reduction of microvascular complications. First-generation SUR represents 3% of used oral hypoglycemic agents while second and third generations are used in about 25% in patients with Type 2 diabetes mellitus. Upregulation of SUR1 receptor has been observed after stroke and traumatic brain injury, therefore, SUR such as glibenclamide inhibits brain edema and astrocyte swelling following brain insults. SUR drugs mainly glibenclamide is effective at a low dose in the management of cerebral stroke and could be a contestant with corticosteroid in controlling brain edema

Role of fenofibrate in multiple sclerosis

Abstract Multiple sclerosis (MS) is the most frequent inflammatory and demyelinating disease of the central nervous system (CNS). The underlying pathophysiology of MS is the destruction of myelin sheath by immune cells. The formation of myelin plaques, inflammation, and injury of neuronal myelin sheath characterizes its neuropathology. MS plaques are multiple focal regions of demyelination disseminated in the brain's white matter, spinal cords, deep grey matter, and cerebral cortex. Fenofibrate is a peroxisome proliferative activated receptor alpha (PPAR-α) that attenuates the inflammatory reactions in MS. Fenofibrate inhibits differentiation of Th17 by inhibiting the expression of pro-inflammatory signaling. According to these findings, this review intended to illuminate the mechanistic immunoinflammatory role of fenofibrate in mitigating MS neuropathology. In conclusion, fenofibrate can attenuate MS neuropathology by modulating different pathways, including oxidative stress, autophagy, mitochondrial dysfunction, inflammatory-signaling pathways, and neuroinflammation

Autophagy and autophagy signaling in Epilepsy: possible role of autophagy activator

Abstract Autophagy is an explicit cellular process to deliver dissimilar cytoplasmic misfolded proteins, lipids and damaged organelles to the lysosomes for degradation and elimination. The mechanistic target of rapamycin (mTOR) is the main negative regulator of autophagy. The mTOR pathway is involved in regulating neurogenesis, synaptic plasticity, neuronal development and excitability. Exaggerated mTOR activity is associated with the development of temporal lobe epilepsy, genetic and acquired epilepsy, and experimental epilepsy. In particular, mTOR complex 1 (mTORC1) is mainly involved in epileptogenesis. The investigation of autophagy’s involvement in epilepsy has recently been conducted, focusing on the critical role of rapamycin, an autophagy inducer, in reducing the severity of induced seizures in animal model studies. The induction of autophagy could be an innovative therapeutic strategy in managing epilepsy. Despite the protective role of autophagy against epileptogenesis and epilepsy, its role in status epilepticus (SE) is perplexing and might be beneficial or detrimental. Therefore, the present review aims to revise the possible role of autophagy in epilepsy

脑啡肽酶和脑啡肽酶抑制剂对葡萄糖稳态的影响:一个有争议的观点和有前景的领域

Abstract Neprilysin (NEP) is a transmembrane zinc‐dependent metalloproteinase that inactivates various peptide hormones including glucagon‐like peptide 1 (GLP‐1). NEP inhibitors may be effective in the management of type 2 diabetes mellitus (T2DM) by increasing the circulating level of GLP‐1. However, acute‐effect NEP inhibitors may lead to detrimental effects by increasing blood glucose independent of GLP‐1. These findings suggest a controversial point regarding the potential role of NEP inhibitors on glucose homeostasis in T2DM patients. Therefore, this perspective aimed to clarify the controversial points concerning the role of NEP inhibitors on glucose homeostasis in T2DM. NEP inhibitors may lead to beneficial effects by inhibition of NEP, which is involved in the impairment of glucose homeostasis through modulation of insulin resistance. NEP increases dipeptidyl peptidase‐4 (DPP4) activity and contributes to increasing active GLP‐1 proteolysis so NEP inhibitors may improve glycemic control through increasing endogenous GLP‐1 activity and reduction of DPP4 activity. Thus, NEP inhibitors could be effective alone or in combination with antidiabetic agents in treating T2DM patients. However, long‐term and short‐term effects of NEP inhibitors may lead to a detrimental effect on insulin sensitivity and glucose homeostasis through different mechanisms including augmentation of substrates and pancreatic amyloid deposition. These findings are confirmed in animal but not in humans. In conclusion, NEP inhibitors produce beneficial rather than detrimental effects on glucose homeostasis and insulin sensitivity in humans though most of the detrimental effects of NEP inhibitors are confirmed in animal studies