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1.
Article in English | MEDLINE | ID: mdl-38578239

ABSTRACT

INTRODUCTION: Gender-affirming estrogen therapy (GAET) is commonly used for feminization in transgender and non-binary (TNB) individuals, yet the optimal rate of change (ROC) in estradiol levels for cardiovascular health is unclear. We examined the association between serum estradiol levels and cardiovascular-related mortality, adverse events, and risk factors in TNB adults using GAET. METHODS: Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE and Web of Science were systematically searched (inception-April 2023) for original articles reporting serum estradiol levels and cardiovascular-related mortality, adverse events, and risk factors in TNB adults using GAET. Data extraction was completed in duplicate following PRISMA guidelines. Stratified random effects meta-analyses using serum estradiol ROC (serum estradiolbaseline-serum estradiolfollow-up/study duration) was used to assess longitudinal studies (Low:0

2.
J Cancer Res Ther ; 20(1): 216-223, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38554324

ABSTRACT

BACKGROUND: Cytochrome P450 (CYP) comprises a group of phase-I metabolizing enzymes that are important in xenobiotics metabolism. Genetic polymorphism of CYPs has been comprehensively studied for their association with a range of diseases. In this study, we assessed single-nucleotide polymorphism (SNP) of CYP1A, CYP1B, CYP2B, and CYP2C and their role in gastrointestinal (GI) cancer susceptibility in the rural population of Maharashtra. MATERIALS AND METHODS: In this hospital-based case-control study, the association of polymorphism of CYP genes was studied by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The study subjects included 200 clinically confirmed GI cancer patients and equal number of healthy controls. Odds ratio (OR) with 95% confidence interval (CI) and P value were evaluated to find out the level of association, where P ≤ 0.005 was considered statistically significant. RESULTS: After the analysis of CYP1A1*2A (rs4646903), CYP1B1*3 (rs1059836), CYP2B6*5 (rs3211371), CYP2C8*2 (rs11572103), CYP2C9*2 (rs1799853), and CYP2C9*3 (rs1057910), we noticed that variant (T) allele of CYP2B6*5 possessed significantly elevated risk (OR = 4.43; 95% CI: 2.20-8.90; P < 0.0001) of GI cancer in studied population. The genotypic distribution of G/C heterozygote allele of CYP1B1*3 (OR = 0.19, 95% CI = 0.12-0.32; P < 0.0001) and homozygous variant C/C allele (OR = 0.24, 95% CI = 0.13-0.45; P < 0.0001) showed a negative association with the development of GI cancer. CONCLUSION: The findings from this study supported that polymorphism of CYP2B6*5gene may be involved in the development of GI cancer. However, other SNPs of CYP1A, CYP1B, and CYP2C genes did not signify the risk for GI cancer in the studied population of rural Maharashtra.


Subject(s)
Cytochrome P-450 CYP1A1 , Gastrointestinal Neoplasms , Humans , Cytochrome P-450 CYP1A1/genetics , Polymorphism, Single Nucleotide , Cytochrome P-450 CYP2C8/genetics , Cytochrome P-450 CYP2C9/genetics , Case-Control Studies , Cytochrome P-450 CYP2B6/genetics , India/epidemiology , Genotype , Gastrointestinal Neoplasms/genetics , Cytochrome P-450 CYP1B1/genetics
3.
Physiol Rep ; 12(6): e15979, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38490814

ABSTRACT

Postural orthostatic tachycardia syndrome (POTS) is characterized by an excessive heart rate (HR) response upon standing and symptoms indicative of inadequate cerebral perfusion. We tested the hypothesis that during lower body negative pressure (LBNP), individuals with POTS would have larger decreases in cardiac and cerebrovascular function measured using magnetic resonance (MR) imaging. Eleven patients with POTS and 10 healthy controls were studied at rest and during 20 min of -25 mmHg LBNP. Biventricular volumes, stroke volume (SV), cardiac output (Qc), and HR were determined by cardiac MR. Cerebral oxygen uptake (VO2 ) in the superior sagittal sinus was calculated from cerebral blood flow (CBF; MR phase contrast), venous O2 saturation (SvO2 ; susceptometry-based oximetry), and arterial O2 saturation (pulse oximeter). Regional cerebral perfusion was determined using arterial spin labelling. HR increased in response to LBNP (p < 0.001) with no group differences (HC: +9 ± 8 bpm; POTS: +13 ± 11 bpm; p = 0.35). Biventricular volumes, SV, and Qc decreased during LBNP (p < 0.001). CBF and SvO2 decreased with LBNP (p = 0.01 and 0.03, respectively) but not cerebral VO2 (effect of LBNP: p = 0.28; HC: -0.2 ± 3.7 mL/min; POTS: +1.1 ± 2.0 mL/min; p = 0.33 between groups). Regional cerebral perfusion decreased during LBNP (p < 0.001) but was not different between groups. These data suggest patients with POTS have preserved cardiac and cerebrovascular function.


Subject(s)
Postural Orthostatic Tachycardia Syndrome , Humans , Postural Orthostatic Tachycardia Syndrome/diagnostic imaging , Lower Body Negative Pressure , Cardiac Output/physiology , Cerebrovascular Circulation/physiology , Heart Rate/physiology , Blood Pressure/physiology
4.
Front Oncol ; 14: 1307839, 2024.
Article in English | MEDLINE | ID: mdl-38347838

ABSTRACT

Deregulation of the DNA damage response (DDR) plays a critical role in the pathogenesis and progression of many cancers. The dependency of certain cancers on DDR pathways has enabled exploitation of such through synthetically lethal relationships e.g., Poly ADP-Ribose Polymerase (PARP) inhibitors for BRCA deficient ovarian cancers. Though lagging behind that of solid cancers, DDR inhibitors (DDRi) are being clinically developed for haematological cancers. Furthermore, a high proliferative index characterize many such cancers, suggesting a rationale for combinatorial strategies targeting DDR and replicative stress. In this review, we summarize pre-clinical and clinical data on DDR inhibition in haematological malignancies and highlight distinct haematological cancer subtypes with activity of DDR agents as single agents or in combination with chemotherapeutics and targeted agents. We aim to provide a framework to guide the design of future clinical trials involving haematological cancers for this important class of drugs.

6.
Nat Rev Cardiol ; 21(6): 379-395, 2024 06.
Article in English | MEDLINE | ID: mdl-38163814

ABSTRACT

Cardiovascular autonomic dysfunction (CVAD) is a malfunction of the cardiovascular system caused by deranged autonomic control of circulatory homeostasis. CVAD is an important component of post-COVID-19 syndrome, also termed long COVID, and might affect one-third of highly symptomatic patients with COVID-19. The effects of CVAD can be seen at both the whole-body level, with impairment of heart rate and blood pressure control, and in specific body regions, typically manifesting as microvascular dysfunction. Many severely affected patients with long COVID meet the diagnostic criteria for two common presentations of CVAD: postural orthostatic tachycardia syndrome and inappropriate sinus tachycardia. CVAD can also manifest as disorders associated with hypotension, such as orthostatic or postprandial hypotension, and recurrent reflex syncope. Advances in research, accelerated by the COVID-19 pandemic, have identified new potential pathophysiological mechanisms, diagnostic methods and therapeutic targets in CVAD. For clinicians who daily see patients with CVAD, knowledge of its symptomatology, detection and appropriate management is more important than ever. In this Review, we define CVAD and its major forms that are encountered in post-COVID-19 syndrome, describe possible CVAD aetiologies, and discuss how CVAD, as a component of post-COVID-19 syndrome, can be diagnosed and managed. Moreover, we outline directions for future research to discover more efficient ways to cope with this prevalent and long-lasting condition.


Subject(s)
Autonomic Nervous System Diseases , COVID-19 , Cardiovascular Diseases , Humans , COVID-19/complications , COVID-19/physiopathology , COVID-19/epidemiology , Autonomic Nervous System Diseases/physiopathology , Autonomic Nervous System Diseases/etiology , Autonomic Nervous System Diseases/diagnosis , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/epidemiology , Post-Acute COVID-19 Syndrome , SARS-CoV-2
7.
Asian Pac J Cancer Prev ; 25(1): 175-184, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38285782

ABSTRACT

BACKGROUND: The antioxidant enzymes are important cellular components involved in detoxification of reactive oxygen species (ROS) and protect cells from ROS induced oxidative damage. Single nucleotide polymorphisms (SNPs) of antioxidant enzyme coding genes such as superoxide dismutase (SOD) and catalase (CAT) may alter the enzyme activity which can influence susceptibility towards carcinogenesis.  Therefore, the present study was planned to investigate possible SNPs of SOD (SOD1 (Cu,Zn-SOD), SOD2(Mn-SOD), SOD3(EC-SOD) and CAT genes and their possible association with breast cancer risk in rural Indian women. METHODS: In this case-control study, the association of SOD and CAT gene polymorphism was studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The study was conducted among 400 clinically breast cancer patients and 400 healthy women in a population of South-Western Maharashtra. The logistic regression analysis was carried out to calculate Odds ratio (OR) with 95% confidence interval and p-value, where p ≤0.05 was considered as statistically significant. RESULTS: The results of analysis of genotype frequency distribution showed significant association of rs4880 SNP of Mn-SOD with BC risk at homozygous variant (CC/CC) genotype (OR 2.46; 95%CI, 1.61-3.75; p<0.0001) and corresponding frequency of variant (C) allele (OR 1.53; 95%CI, 1.25-1.86; p<0.0001). In CAT gene polymorphisms the variant (T/T) was increased significantly in BC cases as compared to controls (OR 3.45; 95%CI, 2.17-5.50; p<0.0001) along with its variant (T) allele (OR 2.01; 95%CI, 1.63-2.48; p<0.0001). CONCLUSIONS: The results implied that, C/C genotype of SOD2-1183T/C polymorphism and T/T genotype of CAT-262 C/T polymorphism may be associated with an increased breast cancer risk. However, SOD1-251 A/G and SOD3-172 G/A polymorphisms did not show any significant difference in variant homozygous genotypes of patients compared to controls.


Subject(s)
Breast Neoplasms , Catalase , Polymorphism, Single Nucleotide , Superoxide Dismutase-1 , Female , Humans , Antioxidants , Breast Neoplasms/epidemiology , Breast Neoplasms/genetics , Case-Control Studies , Catalase/genetics , Genetic Predisposition to Disease , Genotype , India/epidemiology , Reactive Oxygen Species , Superoxide Dismutase/genetics , Superoxide Dismutase-1/genetics
9.
Sci Total Environ ; 912: 169451, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38143007

ABSTRACT

PM2.5 samples (n = 34) were collected from January to April 2017 over Shillong (25.7°N, 91.9°E; 1064 m amsl), a high-altitude site situated in the northeastern Himalaya. The main aim was to understand the sources, characteristics, and optical properties of local vs long-range transported carbonaceous aerosols (CA) using chemical species and dual carbon isotopes (13C and 14C). Percentage biomass burning (BB)/biogenic fraction (fbio, calculated from 14C) varied from 67 to 92 % (78 ± 7) and correlated well with primary BB tracers like f60, and K+, suggesting BB as a considerable source. Rain events are shown to reduce the fbio fraction, indicating majority of BB-derived CA are transported. Further, δ13C (-26.6 ± 0.4) variability was very low over Shillong, suggesting it's limitations in source apportionment over the study region, if used alone. Average ratio of absorption coefficient of methanol-soluble BrC (BrCMS) to water-soluble BrC (BrCWS) at 365 nm was 1.8, indicating a significant part of BrC was water-insoluble. A good positive correlation between fbio and mass absorption efficiency of BrCWS and BrCMS at 365 nm with the higher slope for BrCMS suggests BB derived water-insoluble BrC was more absorbing. Relative radiative forcing (RRF, 300 to 2500 nm) of BrCWS and BrCMS with respect to EC were 11 ± 5 % and 23 ± 16 %, respectively. Further, the RRF of BrCMS was up to 60 %, and that of BrCWS was up to 22 % with respect to EC for the samples with fbio ≥ 0.85 (i.e., dominated by BB), reflecting the importance of BB in BrC RRF estimation.

11.
Curr Neurol Neurosci Rep ; 23(12): 881-892, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37947962

ABSTRACT

PURPOSE OF REVIEW: Long-COVID is a novel condition emerging from the COVID-19 pandemic. Long-COVID is characterized by symptoms commonly seen in autonomic disorders including fatigue, brain fog, light-headedness, and palpitations. This article will critically evaluate recent findings and studies on Long-COVID and its physiological autonomic manifestations. RECENT FINDINGS: Studies have reported on the prevalence of different symptoms and autonomic disorders in Long-COVID cohorts. Autonomic nervous system function, including both the parasympathetic and sympathetic limbs, has been studied using different testing techniques in Long-COVID patients. While numerous mechanisms may contribute to Long-COVID autonomic pathophysiology, it is currently unclear which ones lead to a Long-COVID presentation. To date, studies have not tested treatment options for autonomic disorders in Long-COVID patients. Long-COVID is associated with autonomic abnormalities. There is a high prevalence of clinical autonomic disorders among Long-COVID patients, with limited knowledge of the underlying mechanisms and the effectiveness of treatment options.


Subject(s)
Autonomic Nervous System Diseases , COVID-19 , Postural Orthostatic Tachycardia Syndrome , Humans , Post-Acute COVID-19 Syndrome , Pandemics , COVID-19/complications , COVID-19/epidemiology , Autonomic Nervous System Diseases/epidemiology , Autonomic Nervous System Diseases/etiology , Autonomic Nervous System , Postural Orthostatic Tachycardia Syndrome/diagnosis , Postural Orthostatic Tachycardia Syndrome/epidemiology
12.
J Am Heart Assoc ; 12(21): e029645, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37929748

ABSTRACT

Background Rapidly consuming water may offer practical orthostatic hypotension therapy. However, its efficacy across disorders remains uncertain. This study aims to assess the impact of rapid 350- to 500-mL water intake on systolic and diastolic blood pressure (BP) and heart rate (HR) through a systematic review and meta-analysis. Methods and Results We systematically reviewed MEDLINE and Embase up to June 2023, including randomized controlled trials and prospective cohort studies. Using random-effects meta-analysis, we calculated pooled mean differences (MDs) for maximum hemodynamic effects of rapid 350- to 500-mL water bolus consumption. Participants with orthostatic hypotension experienced increased systolic BP (MD, 24.18 [95% CI, 15.48-32.88]) and diastolic BP (MD, 11.98 [95% CI, 8.87-15.09]) with decreased HR (MD, -3.46 [95% CI, -5.21 to -1.71]). Similar results were observed in multiple system atrophy and pure autonomic failure subgroup analysis. Healthy participants showed modest increases in systolic BP (MD, 2.33 [95% CI, 1.02-3.64]) and diastolic BP (MD, 2.73 [95% CI, 1.15-4.30]), but HR changes were not significant (MD, -2.06 [95% CI, -5.25 to 1.13]). Water had no significant hemodynamic effects in patients with seated or supine postural tachycardia syndrome, although standing effects were unassessed. Our data do not exclude water's potential standing effect in postural tachycardia syndrome. Conclusions In patients with orthostatic hypotension, rapid water intake elevated short-term systolic BP and diastolic BP, with mild HR reduction when seated or supine. Healthy participants exhibited similar but milder effects. However, patients with postural tachycardia syndrome did not experience these changes in seated or supine positions. Further research is needed to evaluate the promising impact of rapid water ingestion on patients with postural tachycardia syndrome in a standing position, which was not addressed in our study.


Subject(s)
Hypotension, Orthostatic , Postural Orthostatic Tachycardia Syndrome , Humans , Prospective Studies , Hemodynamics , Blood Pressure/physiology , Water
13.
Res Sq ; 2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37790494

ABSTRACT

Purpose: Hyperadrenergic orthostatic hypotension is a subtype of orthostatic hypotension associated with elevated norepinephrine levels upon standing. Our previous study found that this subtype is characterized by less severe autonomic impairment compared to orthostatic hypotension with normal or low norepinephrine levels. However, long-term outcomes have not been determined. Thus, the purpose of this study was to evaluate the all-cause mortality and phenoconversion over 7 years. Methods: In this prospective observational study, 92 patients with orthostatic hypotension were recruited from the Vanderbilt Autonomic Dysfunction Center. 34 patients with upright norepinephrine levels above 600 pg/mL were included in the hyperadrenergic cohort and 58 composed the orthostatic hypotension cohort. Both cohorts were followed for 7 years while assessing all-cause mortality and phenoconversion to neurodegenerative autonomic disorders. Results: Hyperadrenergic patients showed an exaggerated orthostatic increase in norepinephrine to 938 ± 305 pg/mL upon head up tilt despite presenting with impaired autonomic reflexes. The 7-year mortality rate was 35% in the hyperadrenergic cohort compared to 22% in orthostatic hypotension (p = 0.01). The hyperadrenergic cohort had a greater phenoconversion rate to multiple system atrophy (p = 0.04), whereas the orthostatic hypotension cohort had greater phenoconversion to Parkinson's disease and dementia with Lewy bodies. Conclusions: Despite having less severe autonomic impairment, our data suggests that hyperadrenergic orthostatic hypotension has worse clinical outcomes than neurogenic orthostatic hypotension. Patients with hyperadrenergic orthostatic hypotension require careful monitoring, given that this condition may be associated with negative outcomes.

14.
Asian Pac J Cancer Prev ; 24(9): 3065-3075, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37774058

ABSTRACT

BACKGROUND: At present very little information is available on combined effects of DNA repair genes with tumor suppressor gene polymorphisms and their association with cancer susceptibility. No such association studies have been carried out with breast cancer or any other cancer from India. Present study was conducted to study the combined effects of SNPs of XRCC1, XRCC2, XRCC3 with Arg72Pro and Arg249Ser SNPs of TP53 gene in risk of BC in rural parts of India. METHODS: The polymorphisms of Arg194Trp, Arg280His, Arg399Gln of XRCC1, Arg188His of XRCC2 and Thr241Met of  XRCC3 with Arg72Pro and Arg249Ser of TP53 gene polymorphisms was studied by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) method. The association among the polymorphisms with breast cancer risk was studied by Odds ratio within 95% confidence interval and SNP-SNP interaction were confirmed by logistic regression analysis. RESULTS: The results of genotype frequency distribution of XRCC1, XRCC2, XRCC3 genotypes showed positive association between XRCC1 Arg280His polymorphism and BC risk (OR=4.54; 95% CI: 3.36- 6.15; p<0.0001).  Also the heterozygous genotypes Arg188His of XRCC2 (OR=1.58; 95% CI: 1.13- 2.21; p=0.007) and Thr241Met genotype of XRCC3 (OR=2.13; 95% CI: 1.44- 3.13; p=0.0001) were associated with BC risk. The combination of heterozygous Arg280His genotype of XRCC1 along with Arg72Pro genotype of TP53 increased the risk of BC (OR=4.53; 95% CI: 2.85-7.20); p<0.0001). Similarly,  the combined effect of heterozygous Arg/His genotype of XRCC1 with heterozygous Arg/Ser genotype of TP53 at codon 249 showed significant association with increased BC risk (OR=5.08; 95% CI: 2.86-9.04); p<0.0001). CONCLUSION: The findings derived from our study concluded that the heterozygous variant Arg280His genotype of XRCC1 and Thr241Met polymorphism of XRCC3 in combination with heterozygous arginine72proline genotype and heterozygous Arg249Ser polymorphism of TP53 showed significant association with breast cancer risk in Maharashtrian women.


Subject(s)
Breast Neoplasms , Polymorphism, Single Nucleotide , Humans , Female , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Genes, p53 , Case-Control Studies , Genetic Predisposition to Disease , X-ray Repair Cross Complementing Protein 1/genetics , Genotype , Genes, Tumor Suppressor , DNA Repair/genetics , Risk Factors , DNA-Binding Proteins/genetics
15.
Sci Total Environ ; 905: 167155, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37730043

ABSTRACT

Indo-Gangetic Plain (IGP) experiences a heavy load of particulate pollution impacting the 9 % of the global population living in this region. The present study examines the dithiothreitol (DTT) assay-based oxidative potential (OP) of PM2.5 and the major sources responsible for the observed OP over the central IGP (Kanpur) during winter. The volume normalized OP (OPV) of PM2.5 varied from 2.7 to 10 nmol DTT min-1 m-3 (5.5 ± 1.5) and mass normalized OP (OPM) of PM2.5 varied from 19 to 58 pmol DTT min-1 µg-1 (34 ± 8.0), respectively. Major sources of PM2.5 were identified using the positive matrix factorization (PMF) and the contribution of these sources to observed OP was estimated through multivariate linear regression of OPv with PMF-resolved factors. Although the PM2.5 mass was dominated by secondary aerosols (SA, 28 %), followed by crustal dust (CD, 24 %), resuspended fine dust (RFD, 14 %), traffic emissions (TE, 8 %), industrial emissions (IE, 17 %), and trash burning (TB, 9 %), their proportionate contribution to OP (except SA) was different likely due to differences in redox properties of chemical species coming from these sources. The SA showed the highest contribution (23 %) to observed OP, followed by RFD (19 %), IE (8 %), TE & TB (5 %), CD (4 %), and others (36 %). Our results highlight the significance of determining the chemical composition of particulates along with their mass concentrations for a better understanding of the relationship between PM and health impacts. Such studies are still lacking in the literature, and these results have direct implications for making better mitigation strategies for healthier air quality.

17.
Pharm Nanotechnol ; 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37711107

ABSTRACT

INTRODUCTION: Nanomedicine has emerged as a revolutionary regimen for moderating communicable as well as non-communicable diseases. PURPOSE: This study demonstrated the phytosynthesis of silver nanoparticles using M. citrifolia leaf extract (MC-AgNPs) and their in vitro antioxidant, antibacterial and anticancer potential. METHODS: The Biosynthesis of MC-AgNPs was studied by spectroscopy and characterized by SEM, TEM, XRD and FTIR analysis. The antibacterial activity was checked by minimum inhibition concentration assay. The HeLa and MCF-7 cancer cell lines were used to explore the cytotoxicity and genotoxicity activity of biogenic MC-AgNPs. RESULTS: The free radical scavenging potential of MC-AgNPs was studied by in vitro DPPH and ABTS assays, which confirmed significant radical scavenging activity in a dose-dependent manner with IC50 of 17.70 ± 0.36 µg/mL for DPPH and 13.37 ± 3.15 µg/mL for ABTS radicals. The bactericidal effects of MC-AgNPs confirmed by MIC showed 0.1 mg/mL concentration of MC-AgNPs with greater sensitivity for E.coli (93.33 ± 0.89), followed by K. pneumoniae (90.99 ± 0.57), S. aureus (87.26 ± 2.80) and P. aeruginosa strains (44.68 ± 0.73). The cytotoxicity results depicted strong dose and time-dependent toxicity of biogenic MC-AgNPs against cancer cell lines fifty percent inhibitory concentration MC-AgNPs against HeLa cells were 13.56 ± 1.22 µg/mL after 24h and 5.57 ± 0.12 µg/mL after 48 h exposure, likewise 16.86 ± 0.88 µg/mL and 11.60 ± 0.97 µg/mL respectively for MCF-7 cells. CONCLUSIONS: The present study revealed the green synthesis of silver nanoparticles using M. citrifolia and their significant antioxidant, antibacterial and anticancer activities.

18.
Nature ; 621(7980): 840-848, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37674084

ABSTRACT

In both cancer and infections, diseased cells are presented to human Vγ9Vδ2 T cells through an 'inside out' signalling process whereby structurally diverse phosphoantigen (pAg) molecules are sensed by the intracellular domain of butyrophilin BTN3A11-4. Here we show how-in both humans and alpaca-multiple pAgs function as 'molecular glues' to promote heteromeric association between the intracellular domains of BTN3A1 and the structurally similar butyrophilin BTN2A1. X-ray crystallography studies visualized that engagement of BTN3A1 with pAgs forms a composite interface for direct binding to BTN2A1, with various pAg molecules each positioned at the centre of the interface and gluing the butyrophilins with distinct affinities. Our structural insights guided mutagenesis experiments that led to disruption of the intracellular BTN3A1-BTN2A1 association, abolishing pAg-mediated Vγ9Vδ2 T cell activation. Analyses using structure-based molecular-dynamics simulations, 19F-NMR investigations, chimeric receptor engineering and direct measurement of intercellular binding force revealed how pAg-mediated BTN2A1 association drives BTN3A1 intracellular fluctuations outwards in a thermodynamically favourable manner, thereby enabling BTN3A1 to push off from the BTN2A1 ectodomain to initiate T cell receptor-mediated γδ T cell activation. Practically, we harnessed the molecular-glue model for immunotherapeutics design, demonstrating chemical principles for developing both small-molecule activators and inhibitors of human γδ T cell function.


Subject(s)
Butyrophilins , Lymphocyte Activation , Phosphoproteins , Receptors, Antigen, T-Cell, gamma-delta , T-Lymphocytes , Animals , Humans , Antigens, CD/immunology , Antigens, CD/metabolism , Butyrophilins/immunology , Butyrophilins/metabolism , Camelids, New World/immunology , Molecular Dynamics Simulation , Phosphoproteins/immunology , Phosphoproteins/metabolism , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Crystallography, X-Ray , Nuclear Magnetic Resonance, Biomolecular , Thermodynamics
19.
Auton Neurosci ; 248: 103105, 2023 09.
Article in English | MEDLINE | ID: mdl-37393658

ABSTRACT

BACKGROUND: Many patients with postural orthostatic tachycardia syndrome (POTS) are hypovolemic with plasma volume deficits of 10-30 %. Some also have low levels of aldosterone and diminished aldosterone-renin ratios despite elevations in angiotensin II, pointing to potential adrenal dysfunction. To assess adrenal gland responsiveness in POTS, we measured circulating levels of aldosterone and cortisol following adrenocorticotropin hormone (ACTH) stimulation. METHODS: While on a low Na+ diet (∼10 mEq/day), 8 female patients with POTS and 5 female healthy controls (HC) received a low dose (1 µg) ACTH bolus following a baseline blood sample. After 60 min, a high dose (249 µg) infusion of ACTH was administered to ensure maximal adrenal response. Venous aldosterone and cortisol levels were sampled every 30 min for 2 h. RESULTS: Aldosterone increased in both groups in response to ACTH but was not different between POTS vs. HC at 60 min (53.5 ng/dL [37.8-61.8 ng/dL] vs. 46.1 ng/dL [36.7-84.9 ng/dL]; P = 1.000) or maximally (56.4 ng/dL [49.2-67.1 ng/dL] vs. 49.5 ng/dL [39.1-82.8 ng/dL]; P = 0.524). Cortisol increased in both groups in response to ACTH but was not different in patients with POTS vs. HC at 60 min (39.9 µg/dL [36.1-47.7 µg/dL] vs. 39.3 µg/dL [35.4-46.6 µg/dL]; P = 0.724) or maximally (39.9 µg/dL [33.9-45.4 µg/dL] vs. 42.0 µg/dL [37.6-49.7 µg/dL]; P = 0.354). CONCLUSIONS: ACTH appropriately increased the aldosterone and cortisol levels in patients with POTS. These findings suggest that the response of the adrenal cortex to hormonal stimulation is intact in patients with POTS.


Subject(s)
Adrenal Glands , Adrenocorticotropic Hormone , Postural Orthostatic Tachycardia Syndrome , Adrenal Glands/drug effects , Humans , Adrenocorticotropic Hormone/administration & dosage , Adrenocorticotropic Hormone/pharmacology , Postural Orthostatic Tachycardia Syndrome/drug therapy , Aldosterone/blood , Case-Control Studies , Hypovolemia , Hydrocortisone/blood , Male , Female , Adult , Middle Aged
20.
Tissue Cell ; 84: 102163, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37487255

ABSTRACT

The exchange of biological material between the neighbouring cells is essential for homeostasis. In pathological conditions, such as cancer, the major challenge in cancer treatment is the abnormal expression of crucial proteins and miRNA exchanged between the cancer cells through extracellular vesicles called exosomes. Clinically, it has been noticed that the primary tumour and the distal metastases are interconnected and co-dependent. The exosomes are key factors responsible for preparing the pre-metastatic niche and communicating between the tumour and the distal metastatic site. Cancer stem cells (CSCs) are a subpopulation of cancer cells with self-renewal characteristics and are shown to be responsible for metastasis. This study aims to understand the effect of metastatic cell line-derived exosomes and their regulation of CSC marker expressions on primary colon cancer cell lines. We have identified that treatment of primary colon cancer cell lines with metastatic colon cancer cell-derived exosomes has significantly increased the proliferation, colony formation, cell migration, and invasion. In addition, there was a significant increase in the number and size of spheroids following the exosomes treatment. We found that this metastatic phenotype is due to the increased expression of CD133 and DCLK1 in primary colon cancer cells.


Subject(s)
Colonic Neoplasms , Exosomes , Extracellular Vesicles , Humans , Cell Proliferation/genetics , Colonic Neoplasms/genetics , Doublecortin-Like Kinases/genetics , Doublecortin-Like Kinases/metabolism , Neoplastic Stem Cells/metabolism , Protein Serine-Threonine Kinases/genetics , AC133 Antigen/genetics , AC133 Antigen/metabolism
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