A putative interaction between mitochondrial cytochrome c oxidase subunit II (COX II) to lamin A/C and LAP2α in colon epithelial cells.

The lamina is a cage-like structure, composed of lamins, found underneath the inner nuclear membrane (INM). In mammals, Lamins are type V intermediate filaments. Three genes encode seven different lamin proteins. These genes are LMNA, LMNB1 and LMNB2. Lamins are classified into A- and B-types. A-type lamins, Lamin A, Lamin C, Lamin Aδ10 and Lamin C2, are mainly expressed in differentiated tissues. All encodes by the LMNA gene and products of alternative splicing. Recent studies have shown the expression of Lamin A/C in colon crypt epithelia cells. This expression was greater in differentiated epithelial and stem cells than in the proliferation zone. Since 1999, mutations in LMNA have been shown to cause several different inherited diseases in muscle, fat, bone, skin and nerve tissues. LAP2α is one of the strong binding partners to Lamin A/C. LAP2α has a specific function as a non-membrane protein associated with the nucleoskeleton and may help to organize higher order chromatin structure by interacting with Lamin A/C. To understand more about Lamin A/C and LAP2α in colon epithelial development,a Yeast 2-hybrid screen was used to look for novel protein interactions to Lamin A/C and/or LAP2a. It was found Cytochrome c oxidase subunit II (Cox2) is a putative binding partner to Lamin A/C and LAP2 α. Cox2 is encoded by the mitochondrial genome and imported into complex IV (COX) of the mitochondrial respiratory chain (MRC). The majority of mitochondrial proteins are encoded by nuclear DNA. However, 13 essential subunits of the MRC are encoded by mtDNA. The MRC is composed of five multi-subunit complexes (I-V). MRC is implicated in ATP generation and is involved in apoptosis in response to different stimuli. Deficiency in COX in colon cancer cells results in resistance to apoptosis and increases in reactive oxygen species (ROS). Biochemical assays like Coimmunopreciptation (IP) and western blot (WB) and Immuno-gold labeling (TEM) were used. IP confirmed the putative interaction of Cox2 to Lamin A/C and LAP2α. WB showed the expression of lamin A/C and LAP2α in the mitochondrial and nuclear fractions but not in cytosol. TEM is alternative method showed the distribution of lamin A/C and LAP2α in the nucleus and mitochondria

L5 Spinal Nerve Axotomy Induces Distinct Electrophysiological Changes in Axotomized L5- and Adjacent L4-Dorsal Root Ganglion Neurons in Rats .

Peripheral neuropathic pain (PNP) is a major health problem for which effective drug treatment is lacking. Its underlying neuronal mechanisms are still illusive, but pre-clinical studies using animal models of PNP including the L5-spinal nerve axotomy (L5-SNA) model, suggest that it is partly caused by excitability changes in dorsal root ganglion (DRG) neurons. L5-SNA results in two DRG neuronal groups: (1) axotomized/damaged neurons in L5- plus some in L4-DRGs, and (2) ipsilateral L4-neurons with intact/uninjured fibers intermingling with degenerating L5-fibers. The axotomized neurons are deprived of peripherally derived trophic factors and degenerate causing neuroinflammation, whereas the uninjured L4-neuorns are subject to increased trophic factors and neuroinflammation associated with Wallerian degeneration of axotomized L5-nerve fibers. Whether these two groups of DRG neurons exhibit similar or distinct electrophysiological changes after L5-SNA remains unresolved. Conflicting evidence for this may result from some studies assuming that all L4-fibers are undamaged. Here, we recorded somatic action potentials (APs) intracellularly from C- and A-fiber L4/L5 DRG neurons to examine our hypothesis that L5-SNA would induce distinct electrophysiological changes in the two populations of DRG neurons. Consistent with this hypothesis, we found (7 days post-SNA), in SNA rats with established pain hypersensitivity, slower AP kinetics in axotomized L5-neurons and faster AP kinetics in L4-nociceptive neurons including decreased rise time in Aδ-and Aβ-fiber nociceptors, and after-hyperpolarization duration in Aβ-fiber nociceptors. We also found several changes in axotomized L5-neurons but not in L4-nociceptive neurons, and some changes in L4-nociceptive but not L5-neurons. The faster AP kinetics (decreased refractory period) in L4-nociceptive neurons that are consistent with their reported hyperexcitability may lead to repetitive firing and thus provide enhanced afferent input necessary for initiating and/or maintaining PNP development. The changes in axotomized L5-neurons may contribute to the central mechanisms of PNP via enhanced neurotransmitter release in the central nervous system (CNS)

Farnesol attenuates cadmium-induced kidney injury by mitigating oxidative stress, inflammation and necroptosis and upregulating cytoglobin and PPARγ in rats

Heavy metals are environmental pollutants that can harm animals and humans even at low concentrations. Cadmium (Cd) is known for its serious health effects on different organs and its toxicity is associated with oxidative stress (OS) and inflammation. Farnesol (FAR), a sesquiterpene alcohol found in many vegetables and fruits, possesses promising anti-inflammatory and antioxidant activities. This study evaluated the effect of FAR on Cd-induced kidney injury, pinpointing its effect of the redox status, inflammation, fibrosis and necroptosis. Rats in this study received FAR for 14 days and Cd on day 7. Elevated serum creatinine, urea and uric acid, and several kidney histopathological alterations were observed in Cd-administered rats. Cd increased MDA, decreased antioxidants, downregulated PPARγ and upregulated NF-κB p65, IL-6, TNF-α, and IL-1β. Necroptosis mediators (RIP1, RIP3, MLKL, and caspase-8) and α-SMA were upregulated, and collagen deposition was increased in Cd-administered rats. FAR ameliorated kidney injury markers and tissue damage, attenuated OS, suppressed NF-κB and inflammatory mediators, and enhanced antioxidants. In addition, FAR suppressed RIP1, RIP3, MLKL, caspase-8, and α-SMA, and enhanced kidney cytoglobin and PPARγ. In conclusion, FAR protects against Cd nephrotoxicity by suppressing OS, inflammatory response and necroptosis, effects associated with enhanced antioxidants, cytoglobin, and PPARγ

Umbelliferone inhibits spermatogenic defects and testicular injury in lead-intoxicated rats by suppressing oxidative stress and inflammation, and improving Nrf2/HO-1 signaling

© 2020 Alotaibi et al. Introduction: Lead (Pb) is an environmental toxic metal that threatens human health. Umbelliferone (UMB) is a coumarin with known medicinal and protective properties against cytotoxicity. This study explored the ameliorative effect of UMB against Pb-induced testicular toxicity in rats, focusing on steroidogenesis, oxidative stress and inflammation. Materials and Methods: Rats received lead acetate (50 mg/kg) and UMB (25, 50 or 100 mg/kg) via oral gavage for 4 weeks. Results: Pb-intoxicated rats exhibited testicular tissue injury and decreased serum levels of LH, FSH and testosterone. The count, viability, motility and normal morphology of the sperms were decreased accompanied with downregulated steroidogenesis markers in Pbinduced group. UMB prevented testicular injury, increased serum levels of LH, FSH and testosterone, upregulated steroidogenesis markers and improved the semen quality. In addition, UMB attenuated oxidative stress and oxidative DNA damage, downregulated the expression of pro-inflammatory mediators and Bax, boosted antioxidant defenses and Bcl2, and upregulated Nrf2/HO-1 signaling in Pb-intoxicated rats. Conclusion: UMB prevents Pb-induced testicular injury by suppressing oxidative damage, inflammation and cell death, and boosting antioxidant defenses, Nrf2/HO-1 signaling and pituitary-gonadal axis. Thus, UMB may represent a protective and cost-effective agent against Pb testicular toxicity, pending further investigations to elucidate other underlying mechanisms.Open Access funding provided by the Qatar National Library

Virulence genes expression among methicillin-resistant staphylococcus aureusisolated form cancer and non-cancer patients

Relative quantitative real-time reverse transcriptase polymerase chain reaction (qPCR) assay was designed and applied in order to study the expression levels of selected genes encoding the adherence and toxins virulent factors. Relative quantification qPCR showed a significant higher expression level of common genes tested among strains isolated from cancer patients not only within the clone but also among different lineages. This study demonstrated that although all MRSA strains studied from cancer and non-cancer patients possessed several virulence determinantsthe expression rather than presence of virulence determinants may mediate higher pathogenicity potential. These data will aid in developing more effective infection control strategy to improve the management of MRSA infection in cancer patients

Mechanistic insights into carbonic anhydrase IX inhibition by coumarins from Calendula officinalis: in vitro and in silico approaches †

Given the critical role of carbonic anhydrase IX (CA IX) in various pathological conditions, there is a significant demand for new inhibitors to enhance patient outcomes and clinical management. In this study, we examined the inhibitory effectiveness of five coumarins derived from Calendula officinalis against CA IX using in vitro assays and computational modeling. Among the coumarins tested, xeroboside and isobaisseoside were identified as the most potent inhibitors. Kinetic studies indicated that xeroboside and isobaisseoside exhibit a mixed inhibition mode. Molecular docking analysis showed that the tested coumarins exhibit binding affinities and extensive polar interactions with CA IX. These coumarins demonstrated significant hydrophobic interactions and occupied the same binding site as acetazolamide (AAZ). Molecular dynamics (MD) indicated that xeroboside and isobaisseoside exhibited consistent trajectories and notable energy stabilization during their interaction with CA IX. MM/PBSA calculations showed that xeroboside displayed the lowest binding free energy (−27.26 ± 2.48 kJ mol−1). Potential Energy Landscape (PEL) analysis revealed distinct and stable conformational states for the CA IX–ligand complexes, with xeroboside exhibiting the most stable and lowest energy configuration. These computational findings are consistent with the experimental results, highlighting the potential efficacy of xeroboside and isobaisseoside as CA IX inhibitors. In conclusion, Calendula officinalis-derived coumarins are promising candidates as effective CA IX inhibitors

Leukotriene B4 mediates p47phox phosphorylation and membrane translocation in polyunsaturated fatty acidâ stimulated neutrophils

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142119/1/jlb0976.pd

The sesquiterpene alcohol farnesol mitigates cadmium hepatotoxicity by attenuating oxidative stress and NF-κB/NLRP3 inflammasome axis and upregulating PPARγ in rats

Farnesol (FAR) is a sesquiterpene alcohol that exists in many fruits and vegetables and possesses promising anti-inflammatory and antioxidant activities. Cadmium (Cd) is an environmental pollutant known for its serious health effects. Liver injury associated with oxidative stress is a hazardous consequence of exposure to Cd. This study evaluated the effect of FAR on Cd-induced oxidative stress, inflammation, and hepatocyte injury, pinpointing the involvement of NF-κB/NLRP3 inflammasome axis, TGF-β/Smad3 signaling and PPARγ. FAR was supplemented for 14 days and rats received Cd on day 7. Elevated serum transaminases, ALP and LDH, decreased albumin, and multiple histopathological alterations were observed in Cd-administered rats. Cd increased liver MDA and NO, decreased GSH and antioxidant enzymes, and upregulated NF-κB p65, IL-6, TNF-α, iNOS, NLRP3, ASC, caspase-1, IL-1β, and cleaved caspase-3. TGF-β, Smad3 phosphorylation and α-SMA were upregulated, and collagen deposition was increased in Cd-administered rats. FAR ameliorated liver injury markers and tissue alterations, attenuated oxidative stress, suppressed NF-κB/NLRP3 inflammasome axis and TGF-β/Smad3 signaling, and enhanced antioxidants. In addition, FAR downregulated caspase-3 and pro-inflammatory cytokines and increased liver PPARγ in Cd-administered rats. In silico, FAR showed affinity to bind ASC and NLRP3 PYD domains, TGF-β, and PPARγ. In conclusion, FAR protects the liver against Cd toxicity by suppressing oxidative stress, inflammatory response and cell death, effects linked to modulation of NF-κB/NLRP3 inflammasome axis, TGF-β/Smad3 signaling and PPARγ

Diallyl Disulfide Mitigates Cadmium Hepatotoxicity by Attenuating Oxidative Stress and TLR-4/NF-κB Signaling and Upregulating PPARγ

Background: Heavy metals can cause serious health problems that affect different organs. Cadmium (Cd) is an environmental contaminant known for its toxicological consequences on different organs. Hepatotoxicity is a serious effect of exposure to Cd with oxidative stress (OS) and inflammation playing a central role. Diallyl disulfide (DADS), an organo-sulfur compound found in garlic, is known for its cytoprotective and antioxidant effects. In this study, the effect of DADS on Cd-induced inflammation, oxidative stress and liver injury was investigated. Methods: DADS was supplemented for 14 days via oral gavage, and a single intraperitoneal dose of Cd (1.2 mg/kg body weight) was administered to rats on day 7. Blood and liver samples were collected at the end of the experiment for analyses. Results: Cd administration resulted in remarkable hepatic dysfunction, degenerative changes, necrosis, infiltration of inflammatory cells, collagen deposition and other histopathological alterations. Cd increased liver malondialdehyde (MDA) and nitric oxide (NO) (p < 0.001), upregulated toll-like receptor (TLR)-4, nuclear factor-kappaB (NF-κB), pro-inflammatory mediators, and caspase-3 (p < 0.001) whereas decreased glutathione (GSH) and antioxidant enzymes (p < 0.001). Cd downregulated peroxisome proliferator activated receptor gamma (PPARγ), a transcription factor involved in inflammation and OS suppression (p < 0.001). DADS ameliorated liver injury and tissue alterations, attenuated OS and apoptosis, suppressed TLR-4/NF-κB signaling, and enhanced antioxidants. In addition, DADS upregulated PPARγ in the liver of Cd-administered rats. Conclusions: DADS is effective against Cd-induced hepatotoxicity and its beneficial effects are linked to suppression of inflammation, OS and apoptosis and upregulation of PPARγ. DADS could be valuable to protect the liver in individuals at risk of Cd exposure, pending further studies to elucidate other underlying mechanism(s)

Lack of Effect of Sleep Apnea on Oxidative Stress in Obstructive Sleep Apnea Syndrome (OSAS) Patients

PURPOSE: The aim of this study was to evaluate markers of systemic oxidative stress and antioxidant capacity in subjects with and without OSAS in order to investigate the most important factors that determine the oxidant-antioxidant status. METHODS: A total of 66 subjects referred to our Sleep laboratory were examined by full polysomnography. Oxidative stress and antioxidant activity were assessed by measurement of the derivatives of reactive oxygen metabolites (d-ROMs) and the biological antioxidant capacity (BAP) in blood samples taken in the morning after the sleep study. Known risk factors for oxidative stress, such as age, sex, obesity, smoking, hypelipidemia, and hypertension, were investigated as possible confounding factors. RESULTS: 42 patients with OSAS (Apnea-Hypopnea index >15 events/hour) were compared with 24 controls (AHI<5). The levels of d-ROMS were significantly higher (p = 0.005) in the control group but the levels of antioxidant capacity were significantly lower (p = 0.004) in OSAS patients. The most important factors predicting the variance of oxidative stress were obesity, smoking habit, and sex. Parameters of sleep apnea severity were not associated with oxidative stress. Minimal oxygen desaturation and smoking habit were the most important predicting factors of BAP levels. CONCLUSION: Obesity, smoking, and sex are the most important determinants of oxidative stress in OSAS subjects. Sleep apnea might enhance oxidative stress by the reduction of antioxidant capacity of blood due to nocturnal hypoxia