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Parkinson's disease (PD) is a chronic neurodegenerative disease characterized by progressive loss of dopamine-producing neurons from the substantia nigra region of the brain. Mitochondrial dysfunction is one of the major causes of oxidative stress and neuronal cell death in PD. E3 ubiquitin ligases such as Parkin (PRKN) modulate mitochondrial quality control in PD; however, the role of other E3 ligases associated with mitochondria in the regulation of neuronal cell death in PD has not been explored. The current study investigated the role of TRIM32, RING E3 ligase, in sensitization to oxidative stress-induced neuronal apoptosis. The expression of TRIM32 sensitizes SH-SY5Y dopaminergic cells to rotenone and 6-OHDA-induced neuronal death, whereas the knockdown increased cell viability under PD stress conditions. The turnover of TRIM32 is enhanced under PD stress conditions and is mediated by autophagy. TRIM32 translocation to mitochondria is enhanced under PD stress conditions and localizes on the outer mitochondrial membrane. TRIM32 decreases complex-I assembly and activity as well as mitochondrial reactive oxygen species (ROS) and ATP levels under PD stress. Deletion of the RING domain of TRIM32 enhanced complex I activity and rescued ROS levels and neuronal viability under PD stress conditions. TRIM32 decreases the level of XIAP, and co-expression of XIAP with TRIM32 rescued the PD stress-induced cell death and mitochondrial ROS level. In conclusion, turnover of TRIM32 increases during stress conditions and translocation to mitochondria is enhanced, regulating mitochondrial functions and neuronal apoptosis by modulating the level of XIAP in PD., (© 2024 Federation of European Biochemical Societies.)

Shifts in the magnitude and nature of gut microbial metabolites have been implicated in Alzheimer's disease (AD), but the host receptors that sense and respond to these metabolites are largely unknown. Here, we develop a systems biology framework that integrates machine learning and multi-omics to identify molecular relationships of gut microbial metabolites with non-olfactory G-protein-coupled receptors (termed the "GPCRome"). We evaluate 1.09 million metabolite-protein pairs connecting 408 human GPCRs and 335 gut microbial metabolites. Using genetics-derived Mendelian randomization and integrative analyses of human brain transcriptomic and proteomic profiles, we identify orphan GPCRs (i.e., GPR84) as potential drug targets in AD and that triacanthine experimentally activates GPR84. We demonstrate that phenethylamine and agmatine significantly reduce tau hyperphosphorylation (p-tau181 and p-tau205) in AD patient induced pluripotent stem cell-derived neurons. This study demonstrates a systems biology framework to uncover the GPCR targets of human gut microbiota in AD and other complex diseases if broadly applied., Competing Interests: Declaration of interests J.B.L. has received consulting fees from Vaxxinity and grant support from GE Healthcare and serves on a data safety monitoring board for Eisai., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Parkinson's Disease (PD) is a chronic neurodegenerative disorder characterized by progressive loss of midbrain dopaminergic neurons in the substantia nigra part of the brain. Pathology spread to numerous brain regions and cell types suggests that intercellular communication is essential to PD progression. Exosomes mediate intercellular communication between neurons, glia, and other cell types throughout PD-relevant brain regions. However, the mechanism remains unclear, and its implication in PD pathology, is not well understood. In the current study, we explored the role of exosomes in modulating the response to PD-relevant toxicants. In cellular models of PD, neuronal cell-derived exosomes are readily internalized by recipient neuronal cells as intact vesicles. Internalized exosomes in bystander neuronal cells localize to mitochondria and dysregulate mitochondrial functions, leading to cell death under PD stress conditions. NGS analysis of exosomes released by neuronal cells subjected to PD stress conditions showed that levels of specific miRNAs were altered in exosomes under PD stress conditions. Bioinformatic analysis of the miRNA targets revealed enriched pathways related to neuronal processes and morphogenesis, apoptosis and ageing. Levels of two miRNAs, hsa-miR-30a-5p and hsa-miR-181c-5p, were downregulated in exosomes under PD stress conditions. Expression of the identified miRNAs in neuronal cells led to their enrichment in exosomes, and exosome uptake in neuronal cells ameliorated mitochondrial dysfunction induced by PD stress conditions and rescued cell death. In conclusion, loss of enrichment of specific miRNAs, including miR-30a-5p and miR-181c-5p, under PD stress conditions causes mitochondrial dysfunction and neuronal death, and hence may lead to progression of PD., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tumor microenvironment (TME) of solid tumors including breast cancer is complex and contains a distinct cytokine pattern including TNF-α, which determines the progression and metastasis of breast tumors. The metastatic potential of triple negative breast cancer subtypes is high as compared to other subtypes of breast cancer. NF-κB is key transcription factor regulating inflammation and mitochondrial bioenergetics including oxidative phosphorylation (OXPHOS) genes which determine its oxidative capacity and generating reducing equivalents for synthesis of key metabolites for proliferating breast cancer cells. The differential metabolic adaptation and OXPHOS function of breast cancer subtypes in inflammatory conditions and its contribution to metastasis is not well understood. Here we demonstrated that different subunits of NF-κB are differentially expressed in subtypes of breast cancer patients. RELA, one of the major subunits in regulation of the NF-κB pathway is positively correlated with high level of TNF-α in breast cancer patients. TNF-α induced NF-κB regulates the expression of LYRM7, an assembly factor for mitochondrial complex III. Downregulation of LYRM7 in MDA-MB-231 cells decreases mitochondrial super complex assembly and enhances ROS levels, which increases the invasion and migration potential of these cells. Further, in vivo studies using Infliximab, a monoclonal antibody against TNF-α showed decreased expression of LYRM7 in tumor tissue. Large scale breast cancer databases and human patient samples revealed that LYRM7 levels decreased in triple negative breast cancer patients compared to other subtypes and is determinant of survival outcome in patients. Our results indicate that TNF-α induced NF-κB is a critical regulator of LYRM7, a major factor for modulating mitochondrial functions under inflammatory conditions, which determines growth and survival of breast cancer cells., Competing Interests: Declaration of competing interest Authors declare no conflict of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Alzheimer's disease (AD) is a chronic neurodegenerative disease needing effective therapeutics urgently. Sildenafil, one of the approved phosphodiesterase-5 inhibitors, has been implicated as having potential effect in AD., Objective: To investigate the potential therapeutic benefit of sildenafil on AD., Methods: We performed real-world patient data analysis using the MarketScan® Medicare Supplemental and the Clinformatics® databases. We conducted propensity score-stratified analyses after adjusting confounding factors (i.e., sex, age, race, and comorbidities). We used both familial and sporadic AD patient induced pluripotent stem cells (iPSC) derived neurons to evaluate the sildenafil's mechanism-of-action., Results: We showed that sildenafil usage is associated with reduced likelihood of AD across four new drug compactor cohorts, including bumetanide, furosemide, spironolactone, and nifedipine. For instance, sildenafil usage is associated with a 54% reduced incidence of AD in MarketScan® (hazard ratio [HR] = 0.46, 95% CI 0.32- 0.66) and a 30% reduced prevalence of AD in Clinformatics® (HR = 0.70, 95% CI 0.49- 1.00) compared to spironolactone. We found that sildenafil treatment reduced tau hyperphosphorylation (pTau181 and pTau205) in a dose-dependent manner in both familial and sporadic AD patient iPSC-derived neurons. RNA-sequencing data analysis of sildenafil-treated AD patient iPSC-derived neurons reveals that sildenafil specifically target AD related genes and pathobiological pathways, mechanistically supporting the beneficial effect of sildenafil in AD., Conclusions: These real-world patient data validation and mechanistic observations from patient iPSC-derived neurons further suggested that sildenafil is a potential repurposable drug for AD. Yet, randomized clinical trials are warranted to validate the causal treatment effects of sildenafil in AD.

So far, the cardio-protective potential of antidiabetics is proved, but their effect on cardiovascular complications associated with cancer cachexia is not explored until now. Insulin resistance and glucose intolerance along with systemic inflammation are prominent in cachexia but the potential effect of antidiabetic agents especially those belonging to biguanide, DPP4 inhibitors and SGLT2 on the heart are not studied till now. In present study, the effect of metformin, vildagliptin, teneligliptin, dapagliflozin and empagliflozin on cardiovascular complications associated with cancer cachexia by using B16F1 induced metastatic cancer cachexia and urethane-induced cancer cachexia was studied. These antidiabetic agents proved to be beneficial against cachexia-induced atrophy of the heart, preserved ventricular weights, maintained cardiac hypertrophic index, preserved the wasting of cardiac muscles assessed by HE staining, Masson trichrome staining, periodic acid Schiff staining and picro-Sirius red staining. Altered cardiac gene expression was attenuated after treatment with selected antidiabetics, thus preventing cardiac atrophy. Also, antidiabetic agents treatment improved the serum creatinine kinase MB, Sodium potassium ATPase and collagen in the heart. Reduction in blood pressure and heart rate was observed after treatment with antidiabetic agents. Results of our study show that the selected antidiabetics prove to be beneficial in attenuating the cardiac atrophy and helps in regulation of hemodynamic stauts in cancer cachexia-induced cardiovascular complications. Our study provides some direction towards use of selected antidiabetic agents in the management of cardiovascular complications associated with cancer cachexia and the study outcomes can be useful in desiging clinical trials., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Stroke is one of the major causes of death and disabilities worldwide. The rapid induction of cell death by necrosis and apoptosis is observed at the ischemic core, while long lasting apoptosis and brain inflammation continue in the penumbra. The emerging evidence suggests a critical role of mitochondria in acute and chronic inflammation and cell death. Mitochondrial dysfunction may result in the release of mitokines and/or mitochondrial DNA into the cytoplasm and activate multiple cytosolic pathways which in turn triggers inflammation. The role of miRNA, specifically mitochondria-associated miRNAs (mitomiRs) in the regulation of mitochondrial functions is emerging. In the current study, we hypothesized that ischemia-induced mitomiRs may modulate the mitochondrial functions and such alterations under stress conditions may lead to mitochondrial dysfunction and cell death. We have demonstrated the specific pattern of miRNAs associated with mitochondria that is altered under ischemic condition induced by transient middle artery occlusion (tMCAo) in rats. The putative targets of altered miRNAs include several mitochondrial proteins which signifies their involvement in maintaining mitochondrial homeostasis. The alteration of selected miRNAs in mitochondria was further detected in a cellular models when hypoxia was induced using a chemical agent CoCl 2 , in three cell lines. Two candidate mitomiRs, hsa-miR-149-3p and hsa-miR-204-5p were further analyzed for their functional role during in vitro hypoxia by transfecting mitomiR mimics into cells and determining critical mitochondrial functions and cell viability. The results here emphasize the role of certain mitomiRs as an important modulator of mitochondrial function under the ischemic condition., Competing Interests: Declaration of competing interest The authors report no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Triple-negative breast cancer is aggressive and metastatic breast cancer type and shows immune evasion, drug resistance, relapse and poor survival. Anti-cancer therapy like ionizing radiation and chemotherapeutic drug majorly induces DNA damage hence, alteration in DNA damage repair and downstream pathways may contribute to tumor cell survival. DNA damage during chemotherapy is sensed by cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes (STING), which determines the anti-tumor immune response by modulating the expression of programmed cell death ligand-1 (PD-L1), immune suppressor, in the tumor microenvironment. Triple-negative breast cancer cells are cGAS-STING positive and modulation of this pathway during DNA damage response for survival and immune escape mechanism is not well understood. Here we demonstrate that doxorubicin-mediated DNA damage induces STING mediated NF-κB activation in triple-negative as compared to ER/PR positive breast cancer cells. STING-mediated NF-κB induces the expression of IL-6 in triple-negative breast cancer cells and activates pSTAT3, which enhances cell survival and PD-L1 expression. Doxorubicin and STAT3 inhibitor act synergistically and inhibit cell survival and clonogenicity in triple-negative breast cancer cells. Knockdown of STING in triple-negative breast cancer cells enhances CD8 mediated immune cell death of breast cancer cells. The combinatorial treatment of triple-negative breast cells with doxorubicin and STAT3 inhibitor reduces PD-L1 expression and activates immune cell-mediated cancer cell death. Further STING and IL-6 levels show a positive correlation in breast cancer patients and poor survival outcomes. The study here strongly suggests that STING mediated activation of NF-κB enhances IL-6 mediated STAT3 in triple-negative breast cancer cells which induces cell survival and immune-suppressive mechanism., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Mitochondria are one of the central organelles involved in cellular energy metabolism and play a regulatory role in various human pathologies ranging from inborn errors of metabolism, cancer, inflammation, and infections. Mitochondrial DNA encodes limited number of genes that is not sufficient for its optimal functioning. Hence, mitochondria import ∼1500 of proteins and ncRNAs from the nucleus depending on energy requirement of cell, tissue size, complexity and diversity of functions. Mitochondrial outer membrane can serve as a platform for regulation of local translation of nuclear-encoded mRNAs of mitochondrial proteins (nmRNAmp); however, underlying molecular mechanism for translational regulation of nmRNAmp at mitochondria is unexplored. Emerging evidence now suggest that mitochondria are enriched with specific miRNAs known as mitomiRs, which may be nuclear or mitochondrial DNA encoded. MitomiRs may modulate mitochondrial function and metabolism by fine-tuning protein levels related to mitochondria. The discovery of mitomiRs raised the questions of elucidating molecular pathways for their biogenesis, translocation, action sites and mechanism of action. Here, we have reviewed the existing reports describing the role of mitomiRs in sub mitochondrial compartments and discussed possible molecular mechanisms of mitomiRs in the regulation of nmRNAmp and mitogenome encoded transcripts. Further understanding of mitomiRs will uncover their implication in various pathophysiological conditions associated with mitochondria., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. and Mitochondria Research Society. All rights reserved.)

Ubiquitin E3-ligases are recruited at different steps of TNF-α-induced NF-κB activation; however, their role in temporal regulation of the pathway remains elusive. The study systematically identified TRIMs as potential feedback regulators of the TNF-α-induced NF-κB pathway. We further observed that TRIM15 is "late" response TNF-α-induced gene and inhibits the TNF-α-induced NF-κB pathway in several human cell lines. TRIM15 promotes turnover of K63-linked ubiquitin chains in a PRY/SPRY domain-dependent manner. TRIM15 interacts with TAK1 and inhibits its K63-linked ubiquitination, thus NF-κB activity. Further, TRIM15 interacts with TRIM8 and inhibits cytosolic translocation to antagonize TRIM8 modualted NF-κB. TRIM8 and TRIM15 also show functionally inverse correlation in psoriasis condition. In conclusion, TRIM15 is TNF-α-induced late response gene and inhibits TNF-α induced NF-κB pathway hence a feedback modulator to keep the proinflammatory NF-κB pathway under control., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Immune adaptor protein like STING/MITA regulate innate immune response and plays a critical role in inflammation in the tumor microenvironment and regulation of metastasis including breast cancer. Chromosomal instability in highly metastatic cells releases fragmented chromosomal parts in the cytoplasm, hence the activation of STING via an increased level of cyclic dinucleotides (cDNs) synthesized by cGMP-AMP synthase (cGAS). Cyclic dinucleotides 2' 3'-cGAMP and it's analog can potentially activate STING mediated pathways leading to nuclear translocation of p65 and IRF-3 and transcription of inflammatory genes. The differential modulation of STING pathway via 2' 3'-cGAMP and its analog and its implication in breast tumorigenesis is still not well explored. In the current study, we demonstrated that c-di-AMP can activate type-1 IFN response in ER negative breast cancer cell lines which correlate with STING expression. c-di-AMP binds to STING and activates downstream IFN pathways in STING positive metastatic MDA-MB-231/MX-1 cells. Prolonged treatment of c-di-AMP induces cell death in STING positive metastatic MDA-MB-231/MX-1 cells mediated by IRF-3. c-di-AMP induces IRF-3 translocation to mitochondria and initiates Caspase-9 mediated cell death and inhibits clonogenicity of triple-negative breast cancer cells. This study suggests that c-di-AMP can activate and modulates STING pathway to induce mitochondrial mediated apoptosis in estrogen-receptor negative breast cancer cells.

Background: Tumor necrosis factor-α (TNF-α) is an immunostimulatory cytokine that is consistently high in the breast tumor microenvironment (TME); however, its differential role in mitochondrial functions and cell survival in ER/PR +ve and ER/PR -ve breast cancer cells is not well understood., Methods: In the current study, we investigated TNF-α modulated mitochondrial proteome using high-resolution mass spectrometry and identified the differentially expressed proteins in two different breast cancer cell lines, ER/PR positive cell line; luminal, MCF-7 and ER/PR negative cell line; basal-like, MDA-MB-231 and explored its implication in regulating the tumorigenic potential of breast cancer cells. We also compared the activity of mitochondrial complexes, ATP, and ROS levels between MCF-7 and MDA-MB-231 in the presence of TNF-α. We used Tumor Immune Estimation Resource (TIMER) webserver to analyze the correlation between TNF-α and mitochondrial proteins in basal and luminal breast cancer patients. Kaplan-Meier method was used to analyze the correlation between mitochondrial protein expression and survival of breast cancer patients., Results: The proteome analysis revealed that TNF-α differentially altered the level of critical proteins of mitochondrial respiratory chain complexes both in MCF-7 and MDA-MB-231, which correlated with differential assembly and activity of mitochondrial ETC complexes. The inhibition of the glycolytic pathway in the presence of TNF-α showed that glycolysis is indispensable for the proliferation and clonogenic ability of MDA-MB-231 cells (ER/PR -ve) as compared to MCF-7 cells (ER/PR +ve). The TIMER database showed a negative correlation between the expressions of TNF-α and key regulators of mitochondrial OXPHOS complexes in basal breast vs lobular carcinoma. Conversely, patient survival analysis showed an improved relapse-free survival with increased expression of identified proteins of ETC complexes and survival of the breast cancer patients., Conclusion: The evidence presented in our study convincingly demonstrates that TNF-α regulates the survival and proliferation of aggressive tumor cells by modulating the levels of critical assembly factors and subunits involved in mitochondrial respiratory chain supercomplexes organization and function. This favors the rewiring of mitochondrial metabolism towards anaplerosis to support the survival and proliferation of breast cancer cells. Collectively, the results strongly suggest that TNF-α differentially regulates metabolic adaptation in ER/PR +ve (MCF-7) and ER/PR -ve (MDA-MB-231) cells by modulating the mitochondrial supercomplex assembly and activity.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons in the substantia nigra (SN) pars compacta region of the brain. The main pathological hallmark involves cytoplasmic inclusions of α-synuclein and mitochondrial dysfunction, which is observed in other part of the central nervous system other than SN suggesting the spread of pathogenesis to bystander neurons. The inter-neuronal communication through exosomes may play an important role in the spread of the disease; however, the mechanisms are not well elucidated. Mitochondria and its role in inter-organellar crosstalk with multivesicular body (MVB) and lysosome and its role in modulation of exosome release in PD is not well understood. In the current study, we investigated the mitochondria-lysosome crosstalk modulating the exosome release in neuronal and glial cells. We observed that PD stress showed enhanced release of exosomes in dopaminergic neurons and glial cells. The PD stress condition in these cells showed fragmented network and mitochondrial dysfunction which further leads to functional deficit of lysosomes and hence inhibition of autophagy flux. Neuronal and glial cells treated with rapamycin showed enhanced autophagy and inhibited the exosomal release. The results here suggest that maintenance of mitochondrial function is important for the lysosomal function and hence exosomal release which is important for the pathogenesis of PD.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurodegenerative disorder caused by an expansion of 55 to 200 CGG repeats located within 5'UTR of FMR1.These CGG repeats are transcribed into RNAs, which sequester several RNA binding proteins and alter the processing of miRNAs. CGG repeats are also translated into a toxic polyglycine-containing protein, FMRpolyG, that affects mitochondrial and nuclear functions reported in cell and animal models and patient studies. Nuclear-encoded small non-coding RNAs, including miRNAs, are transported to mitochondria; however, the role of mitochondrial miRNAs in FXTAS pathogenesis is not understood. Here, we analyzed mitochondrial miRNAs from HEK293 cells expressing expanded CGG repeats and their implication in the regulation of mitochondrial functions. The analysis of next generation sequencing (NGS) data of small RNAs from HEK293 cells expressing CGG premutation showed decreased level of cellular miRNAs and an altered pattern of association of miRNAs with mitochondria (mito-miRs). Among such mito-miRs, miR-320a was highly enriched in mitoplast and RNA immunoprecipitation of Ago2 (Argonaute-2) followed by Droplet digital PCR (ddPCR)suggested that miR-320a may form a complex with Ago2 and mitotranscripts. Finally, transfection of miR-320a mimic in cells expressing CGG permutation recovers mitochondrial functions and rescues cell death. Overall, this work reveals an altered translocation of miRNAs to mitochondria and the role of miR-320a in FXTAS pathology., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Mitochondrial dysfunction is known to be associated with neurodegenerative diseases (NDDs), which is a major burden on the society. Therefore, understanding the regulation of mitochondrial dysfunctions and its implication in neurodegeneration has been major goal for exploiting these mechanisms to rescue neuronal death. The crosstalk between mitochondria and nucleus is important for different neuronal functions including axonal branching, energy homeostasis, neuroinflammation and neuronal survival. The decreased mitochondria capacity during progressive neurodegeneration leads to the altered OXPHOS activity and generation of ROS. The ROS levels in narrow physiological range can reprogram nuclear gene expression to enhance the cellular survival by phenomenon called mitohormesis. Here, we have systematically reviewed the existing reports of mitochondrial dysfunctions causing altered ROS levels in NDDs. We further discussed the role of ROS in regulating mitohormesis and emphasized the importance of mitohormesis in neuronal homeostasis. The emerging role of mitohormesis highlights its importance in future studies on intracellular ROS mediated rescue of mitochondrial dysfunction along with other prevailing mechanisms to alleviate neurodegeneration., (Copyright © 2020. Published by Elsevier B.V.)

Emerging evidence suggests that ubiquitin mediated post translational modification is a critical regulatory process involved in diverse cellular pathways including cell death. During ubiquitination, E3 ligases recognize target proteins and determine the topology of ubiquitin chains. Recruitment of E3 ligases to targets proteins under stress conditions including oxidative stress and their implication in cell death have not been systemically explored. In the present study, we characterized the role of TRIM32 as an E3 ligase in regulation of oxidative stress induced cell death. TRIM32 is ubiquitously expressed in cell lines of different origin and form cytoplasmic speckle like structures that transiently interact with mitochondria under oxidative stress conditions. The ectopic expression of TRIM32 sensitizes cell death induced by oxidative stress whereas TRIM32 knockdown shows a protective effect. The turnover of TRIM32 is enhanced during oxidative stress and its expression induces ROS generation, loss of mitochondrial transmembrane potential and decrease in complex-I activity. The pro-apoptotic effect was rescued by pan-caspase inhibitor or antioxidant treatment. E3 ligase activity of TRIM32 is essential for oxidative stress induced apoptotic cell death. Furthermore, TRIM32 decreases X-linked inhibitor of apoptosis (XIAP) level and overexpression of XIAP rescued cells from TRIM32 mediated oxidative stress and cell death. Overall, the results of this study provide the first evidence supporting the role of TRIM32 in regulating oxidative stress induced cell death, which has implications in numerous pathological conditions including cancer and neurodegeneration., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an inherited neurodegenerative disorder caused by an expansion of 55-200 CGG repeats at 5UTR of FMR1 gene, known as premutation. The main clinical and neuropathological features of FXTAS include progressive intention tremor, gait ataxia, neuronal cell loss and presence of ubiquitin-positive intranuclear inclusions in neurons and astrocytes. Various mitochondrial dysfunctions are reported in in vitro/vivo models of FXTAS; however, the molecular mechanisms underlying such mitochondrial dysfunctions are unclear. CGG expansions are pathogenic through distinct mechanisms involving RNA gain of function, impaired DNA damage repair and FMRpolyG toxicity. Here, we have systematically reviewed the reports of mitochondrial dysfunctions under premutation condition. We have also focused on potential emerging mechanisms to understand mitochondrial associated pathology in FXTAS. This review highlights the important role of mitochondria in FXTAS and other related disorders; and suggests focus of future studies on mitochondrial dysfunction along with other prevailing mechanisms to alleviate neurodegeneration., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background and Objectives: Laparoscopic sleeve gastrectomy (LSG) currently accounts for 70.1% of weight-loss surgeries in Australia, according to the Bariatric Surgery Registry. There are limited qualitative studies examining Australian patients' experiences. The aim of this study was to explore patients' perspectives following LSG, providing information for shared decision making., Method: Twenty-two patients one, two or three years post-LSG were recruited randomly. Qualitative data were collected through in-depth telephone interviews, and responses were analysed inductively., Results: Three global themes were identified: 1) normality, 2) control and 3) ambivalence, with eight organising sub-themes: 1) weight, 2) physical changes and daily living enhancements, 3) exercise, 4) emotional responses, 5) eating behaviour, 6) societal influences, 7) body image and 8) relationships., Discussion: LSG is generally associated with high levels of patient satisfaction, with physical and psychosocial benefits beyond metabolic improvements. The decision to undergo this elective procedure should be made with an understanding of the significant and permanent effects it has on patients' lives.

Antibiotics are the front-line treatment against many bacterial infectious diseases in human. The excessive and long-term use of antibiotics in human cause several side effects. It is important to understand the underlying molecular mechanisms of action of antibiotics in the host cell to avoid the side effects due to the prevalent uses. In the current study, we investigated the crosstalk between mitochondria and lysosomes in the presence of widely used antibiotics: erythromycin (ERM) and clindamycin (CLDM), which target the 50S subunit of bacterial ribosomes. We report here that both ERM and CLDM induced caspase activation and cell death in several different human cell lines. The activity of the mitochondrial respiratory chain was compromised in the presence of ERM and CLDM leading to bioenergetic crisis and generation of reactive oxygen species. Antibiotics treatment impaired autophagy flux and lysosome numbers, resulting in decreased removal of damaged mitochondria through mitophagy, hence accumulation of defective mitochondria. We further show that over-expression of transcription factor EB (TFEB) increased the lysosome number, restored mitochondrial function and rescued ERM- and CLDM-induced cell death. These studies indicate that antibiotics alter mitochondria and lysosome interactions leading to apoptotsis and may develop a novel approach for targeting inter-organelle crosstalk to limit deleterious antibiotic-induced side effects.

An increased level of proinflammatory cytokines, including TNF-α in tumor microenvironment regulates the bioenergetic capacity, immune evasion and survival of cancer cells. Emerging evidences suggest that mitochondrial immune signaling proteins modulates mitochondrial bioenergetic capacity, in addition to the regulation of innate immune response. The optimal oxidative phosphorylation (OxPhos) capacity is required for the maintenance of functional lysosomes and autophagy flux. NLRX1, a mitochondrial NOD family receptor protein, regulates mitochondrial function during apoptosis and tissue injury. However, its role in regulation of mitochondrial and lysosomal function to modulate autophagy flux during inflammatory conditions is not understood. In the current study, we investigated the role of NLRX1 in modulating TNF-α induced autophagy flux and mitochondrial turnover and its implication in regulating the invasive and metastatic capability of breast cancer cells. Expression analyses of clinical breast cancer samples and meta-analysis of multiple public databases revealed that NLRX1 expression is significantly increased in basal-like and metastatic breast carcinoma as compared to non-basal-like and primary breast cancer. Depletion of NLRX1 expression in triple-negative breast cancer cells, altered the organization and activity of OxPhos complexes in presence of TNF-α. NLRX1 depletion further impaired lysosomal function and hence the turnover of damaged mitochondria through mitophagy in presence of TNF-α. Importantly, loss of NLRX1 decreased OxPhos-dependent cell proliferation and migration ability of triple-negative breast cancer cells in presence of TNF-α. These evidences suggest an essential role of NLRX1 in maintaining the crosstalk of mitochondrial metabolism and lysosomal function to regulate invasion and metastasis capability of breast cancer cells., (Copyright © 2019. Published by Elsevier B.V.)

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an inherited neurodegenerative disorder caused by an expansion of 55 to 200 CGG repeats (premutation) in FMR1. These CGG repeats are Repeat Associated non-ATG (RAN) translated into a small and pathogenic protein, FMRpolyG. The cellular and molecular mechanisms of FMRpolyG toxicity are unclear. Various mitochondrial dysfunctions have been observed in FXTAS patients and animal models. However, the causes of these mitochondrial alterations are not well understood. In the current study, we investigated interaction of FMRpolyG with mitochondria and its role in modulating mitochondrial functions. Beside nuclear inclusions, FMRpolyG also formed small cytosolic aggregates that interact with mitochondria both in cell and mouse model of FXTAS. Importantly, expression of FMRpolyG reduces ATP levels, mitochondrial transmembrane potential, mitochondrial supercomplexes assemblies and activities and expression of mitochondrial DNA encoded transcripts in cell and animal model of FXTAS, as well as in FXTAS patient brain tissues. Overall, these results suggest that FMRpolyG alters mitochondrial functions, bioenergetics and initiates cell death. The further study in this direction will help to establish the role of mitochondria in FXTAS conditions., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The role of mitochondria is emerging in regulation of innate immunity, inflammation and cell death beyond its primary role in energy metabolism. Mitochondria act as molecular platform for immune adaptor protein complexes, which participate in innate immune signaling. The mitochondrial localized immune adaptors are widely expressed in non-immune cells, however their role in regulation of mitochondrial function and metabolic adaption is not well understood. NLRX1, a member of NOD family receptor proteins, localizes to mitochondria and is a negative regulator of anti-viral signaling. However, the submitochondrial localization of NLRX1 and its implication in regulation of mitochondrial functions remains elusive. Here, we confirm that NLRX1 translocates to mitochondrial matrix and associates with mitochondrial FASTKD5 (Fas-activated serine-threonine kinase family protein-5), a bonafide component of mitochondrial RNA granules (MRGs). The association of NLRX1 with FASTKD5 negatively regulates the processing of mitochondrial genome encoded transcripts for key components of complex-I and complex-IV, to modulate its activity and supercomplexes formation. The evidences, here, suggest an important role of NLRX1 in regulating the post-transcriptional processing of mitochondrial RNA, which may have an important implication in bioenergetic adaptation during metabolic stress, oncogenic transformation and innate immunity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In cancer patients, treatment modalities like chemotherapy and radiation exert their anticancer effects by inducing DNA damage. The cancer cells can survive under genotoxic stress by inducing DNA damage response (DDR) or can undergo cell death. The process of autophagy is emerging as crucial regulator of cell survival during different stress conditions. Post translational modification through ubiquitin plays an essential role in DDR during genotoxic stress conditions. Ubiquitin ligases regulate autophagy and cell death pathways however their role during genotoxic stress conditions is not understood. In the current study we identified TRIM8, RING E3 Ligase, as a novel regulator of autophagy during DDR. TRIM8 regulates lysosomal biogenesis and autophagy flux. The turnover of TRIM8 is high and is stabilized during genotoxic stress conditions. TRIM8 regulated autophagy is essential for its cytoprotective role during genotoxic stress induced cell death. TRIM8 stabilizes the turnover of XIAP during genotoxic stress and forms complex with XIAP and caspase-3 to inhibit its activation in presence of etoposide. TRIM8 mediated autophagy promotes degradation of cleaved caspase-3 subunits. This study described TRIM8, as a novel regulator of DDR-autophagy crosstalk, which may play role in survival of cancer cells in presence of genotoxic agents., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The current study deals with the effect of a dietary flavanoid quercetin on fibrotic lung tissue in rats. Bleomycin was administered by single intratracheal instillation to Wistar rats to induce lung fibrosis. The pathologies associated with this included significantly reduced antioxidant capacity, ultimately leading to protracted inflammation of the lung tissue. The hallmark of this induced fibrosis condition was an excessive collagen deposition in peribronchial and perialveolar regions of the lung. Oral quercetin treatment over a period of twenty days resulted in significant reversal of the pathologies. The antioxidant defense in lung tissue was revived. Moreover, activity of the collagenase MMP-7, which was high in fibrotic tissue, was seen restored after quercetin administration. Trichome staining of lung tissue sections showed high collagen deposition in fibrotic rats, which may be a direct result of increased mobilization of collagen by MMP-7. This was appreciably reduced in quercetin treated animals. These results point towards an important protective role of quercetin against idiopathic lung fibrosis, which remains a widely prevalent yet incurable condition in the present times.

Purpose: We assessed the effects of different shock wave delivery rates in patients treated with shock wave lithotripsy for renal stones, particularly treatment success, degree of renal injury and pain experienced, and analgesic demand., Materials and Methods: A total of 206 patients with renal stones were prospectively randomized to receive shock waves delivered at 60 (group 1) or 120 (group 2) shocks per minute using a Sonolith® Vision at a single institution in October 2008 and August 2010. The primary outcome was successful treatment 12 weeks after 1 lithotripsy session. Secondary outcome measures included the degree of renal injury, as reflected by changes in urinary markers of renal injury, as well as patient pain scores and analgesia consumed during treatment., Results: Mean stone size in groups 1 and 2 was 8.95 and 9.28 mm, respectively (p = 0.525). The overall treatment success rate was 43.2%. It was significantly better in group 1 than in group 2 (50.5% vs 35.9%, p = 0.035). There was no between group difference in the success rate for stones 10 mm or less but the success rate was statistically better for group 1 patients with stones greater than 10 mm (p = 0.002). Immediately after shock wave lithotripsy there was a statistically significant greater increase in urinary NAG (p = 0.003) and interleukin-18 (p = 0.022) in group 1. There was no between group difference in pain scores, analgesic consumption during shock wave lithotripsy or unplanned hospital visits., Conclusions: Slower shock wave delivery yielded better treatment outcomes, particularly for stones greater than 10 mm, without increasing patient pain or analgesic demand. However, slower shock wave delivery also appeared to cause a statistically significant increase in acute renal injury markers, although the clinical implication was uncertain., (Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Dictyostelium discoideum, a unicellular eukaryote, exhibits multicellularity upon nutrient starvation and is a good model system for developmental studies, and for the study of various signal transduction pathways. Reactive oxygen species at low doses act as signaling molecules; however, at high doses they are known to cause DNA damage that results in the activation of poly(ADP-ribose) polymerase (PARP). We have earlier reported the high resistance of the unicellular stage of D. discoideum to oxidative stress, and we now show the response of this organism to oxidative stress and the role of PARP during development. We used hydroxylamine (HA) to induce in situ generation of H(2)O(2) and monitored the effect of benzamide, a PARP inhibitor, on oxidative stress-induced changes in D. discoideum development. Interestingly, oxidative stress resulted in PARP activation within 5 min that was inhibited by benzamide. Oxidative stress-induced delay in developmental pattern was also partially restored by benzamide. We studied the long-term effects of PARP inhibition under oxidative stress, and our results demonstrated that spores formed under HA stress exhibited significant delay in germination in comparison to benzamide-pretreated HA-stressed cells. However, second-generation cells showed normal development, signifying that PARP inhibition has no deleterious effect on D. discoideum development under oxidative stress.

Objective: A variety of methods have been used to select and identify fetal cells from maternal blood. In this study, a commonly used 3-step selection method is compared with selection directly from whole blood. Identification of fetal origin by XY FISH of male cells was also evaluated., Methods: Maternal blood was drawn either before invasive chorion villus sampling (pre-CVS) or after (post-CVS) from women carrying a male fetus. Fetal cells were isolated either by density gradient centrifugation succeeded by CD45/CD14 depletion and CD71-positive selection from CD45/CD14-negative cells, or by CD71-positive selection directly from whole blood. The true origin of fetal cells recovered by the two methods was established by two rounds of XY chromosome FISH in reverse colors, in some instances combined with anti-zeta (zeta) or anti-zeta/anti-gamma (gamma) antibody staining., Results: In blood samples taken post-CVS and enriched by CD71 selection directly from whole blood, fetal cells were identified with a frequency that was almost four orders of magnitude higher than in post-CVS samples enriched by the 3-step method. In blood samples taken pre-CVS and enriched by the 3-step procedure, no fetal cells were identified by reverse color FISH in 371 ml of blood. In similar samples enriched by CD71 selection on whole blood, two fetal cells were identified in 27 ml of blood. Rehybridization with X and Y chromosome probes with reverse colors was necessary to exclude false Y chromosome signals. Not all fetal cells identified by the presence of a true Y chromosome signal stained with anti-zeta antibody., Conclusions: Selection of fetal NRBCs from maternal blood by CD71-positive selection directly from whole blood is superior to density gradient centrifugation succeeded by CD45/CD14 depletion and CD71 selection of CD45/CD14-negative cells. Combining two markers for fetal origin is recommended for unambiguously identifying a cell as fetal., (Copyright (c) 2005 S. Karger AG, Basel.)

Two cases are reported in which depression was associated with the use of calcium channel blocker, nifedipine. In one instance, a patient became unresponsive to treatment with nortriptyline when nifedipine was introduced. In both cases, the depression resolved following discontinuation of nifedipine.