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1.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474092

RESUMO

Proteases are critical enzymes in cellular processes which regulate intricate events like cellular proliferation, differentiation and apoptosis. This review highlights the multifaceted roles of the serine proteases FAM111A and FAM111B, exploring their impact on cellular functions and diseases. FAM111A is implicated in DNA replication and replication fork protection, thereby maintaining genome integrity. Additionally, FAM111A functions as an antiviral factor against DNA and RNA viruses. Apart from being involved in DNA repair, FAM111B, a paralog of FAM111A, participates in cell cycle regulation and apoptosis. It influences the apoptotic pathway by upregulating anti-apoptotic proteins and modulating cell cycle-related proteins. Furthermore, FAM111B's association with nucleoporins suggests its involvement in nucleo-cytoplasmic trafficking and plays a role in maintaining normal telomere length. FAM111A and FAM111B also exhibit some interconnectedness and functional similarity despite their distinct roles in cellular processes and associated diseases resulting from their dysfunction. FAM111A and FAM111B dysregulation are linked to genetic disorders: Kenny-Caffey Syndrome type 2 and Gracile Bone Dysplasia for FAM111A and POIKTMP, respectively, and cancers. Therefore, the dysregulation of these proteases in diseases emphasizes their potential as diagnostic markers and therapeutic targets. Future research is essential to unravel the intricate mechanisms governing FAM111A and FAM111B and explore their therapeutic implications comprehensively.


Assuntos
Doenças do Desenvolvimento Ósseo , Nanismo , Humanos , Peptídeo Hidrolases/genética , Mutação , Proteínas de Ciclo Celular/metabolismo , Nanismo/genética , Endopeptidases/genética , Receptores Virais/metabolismo
2.
JAAD Int ; 13: 150-158, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37823040

RESUMO

Androgenetic alopecia (AGA) is the most common nonscarring alopecia and is characterised by distinct gradual patterned hair loss. AGA is mediated by genetic predisposition and excessive follicular sensitivity to androgens, mainly in males, leading to the progressive conversion of scalp terminal hair into vellus hair. Although highly prevalent, it is not fatal but may have a severe psychosocial impact, especially on females and younger males. Significant advances have been made in understanding AGA's epidemiology and pathophysiology, but only 2 drugs remain approved by the FDA - finasteride and minoxidil. Prolonged use of these drugs, is a prerequisite for enhanced treatment response. However, this leads to poor medication adherence and adverse effects from extended use eg, the "postfinasteride syndrome" which persists beyond stopping the drug. Hence, there is a need for research on more effective alternative treatments for AGA, with fewer side effects. This paper reviewed recent advances in AGA pathophysiology and its treatment options. The recently characterized structure of type 2, 5-alpha reductase holds significance in comprehending present and prospective treatments of AGA.

3.
J Physiol ; 601(7): 1287-1306, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36849131

RESUMO

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.


Assuntos
Diabetes Gestacional , Resistência à Insulina , Obesidade Materna , Recém-Nascido , Feminino , Humanos , Gravidez , Placenta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Obesidade Materna/metabolismo , África do Sul , Obesidade/metabolismo , Inflamação , Citocinas/metabolismo
4.
Cancer Treat Res Commun ; 34: 100679, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36610347

RESUMO

INTRODUCTION: Mutations in the uncharacterised human FAM111B gene are associated with POIKTMP, a rare multi-organ fibrosing disease. Recent studies also reported the overexpression of FAM111B in specific cancers. Moreover, FAM111B mutation screening may prove expensive in under-resourced facilities. Therefore, this study investigated its cellular function and dysfunction and described an inexpensive mutation screening method. MATERIALS AND METHODS: FAM111B expression was assessed in silico and validated in vitro in cell lines and primary skin fibroblasts from a South African POIKTMP-patient with the heterozygous FAM111B gene mutation: NM_198947.4: c.1861T>G (p. Tyr621Asp or Y621D) by qPCR and western blot. The cellular function of FAM111B was studied in HT1080 using various cell-based functional assays, and the Y621D mutation was genotyped by PCR-RFLP. RESULTS: Expression studies showed upregulated FAM111B mRNA and protein in the cancer cells. High FAM111B expression with robust nuclear localization occurred in HT1080. Additionally, expression data and cell-based assays indicated that FAM111B led to the upregulation of cell migration, decreased cell apoptosis, and modulatory effects on cell proliferation. Y621D mutation showed similar effects on cell migration but minimal impact on cell apoptosis. FAM111B mRNA and protein expression were markedly downregulated (p ≤ 0.05) in the POIKTMP-patient's fibroblasts. The PCR-RFLP method successfully genotyped Y621D gene mutation. DISCUSSION: FAM111B is a cancer-associated nuclear protein: Its modulation by mutations or overexpression may contribute to the malignancy of cancers and POIKTMP/fibrosis and poor clinical outcomes and represents a viable prognostic marker or therapeutic target. Furthermore, the PCR-RFLP method could prove a valuable tool for FAM111B mutation validation or screening in resource-constrained laboratories.


Assuntos
Proteínas de Ciclo Celular , Fibrossarcoma , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Mutação , Fibrossarcoma/genética , Genótipo , Polimorfismo de Fragmento de Restrição
5.
Front Oncol ; 12: 932167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860584

RESUMO

FAM111B gene mutations are associated with a hereditary fibrosing poikiloderma known to cause poikiloderma, tendon contracture, myopathy, and pulmonary fibrosis (POIKTMP). In addition, the overexpression of FAM111B has been associated with cancer progression and poor prognosis. This review inferred the molecular function of this gene's protein product and mutational dysfunction in fibrosis and cancer based on recent findings from studies on this gene. In conclusion, FAM111B represents an uncharacterized protease involved in DNA repair, cell cycle regulation, and apoptosis. The dysregulation of this protein ultimately leads to fibrotic diseases like POIKTMP and cancers via the disruption of these cellular processes by the mutation of the FAM111B gene. Hence, it should be studied in the context of these diseases as a possible therapeutic target.

6.
Exp Dermatol ; 31(5): 648-654, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35122327

RESUMO

Mutations in the human FAM111B gene are associated with a rare, hereditary multi-systemic fibrosing disease, POIKTMP. To date, there are ten POIKTMP-associated FAM111B gene mutations reported in thirty-six patients from five families globally. To investigate the clinical significance of these mutations, we summarized individual cases by clinical features and position of the reported FAM111B gene mutations as those within and outside the putative protease domain (MWPPD and MOPPD respectively). MWPPD cases had more clinical manifestations than MOPPD (25 versus 18). Although the most common clinical features of poikiloderma, alopecia and hypohidrosis overall occurred in 94%, 86% and 75% of all cases with no significant differences between the MOPPD and MWPPD group, less common features included life-threatening (pulmonary fibrosis 47% vs. 13%; liver abnormalities specifically cirrhosis 26% vs. 7%) and physically disabling conditions (myopathy 53% vs. 20%; tendon contracture 55% vs. 7%) were more common in MWPPD cases. Similarly, the only 2 cases of POIKTMP with fatal pancreatic cancers were both only in the MWPPD group. This review thus suggests that mutations within the putative protease domain of the FAM111B protein are associated with a broader range of clinical features and may predict increased POIKTMP severity and a poorer prognosis.


Assuntos
Dermatopatias Genéticas , Proteínas de Ciclo Celular/genética , Humanos , Mutação , Peptídeo Hidrolases/genética , Índice de Gravidade de Doença , Dermatopatias Genéticas/complicações
7.
Oxid Med Cell Longev ; 2021: 5522981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804368

RESUMO

Neurodegenerative diseases (NDs) like Alzheimer's disease, multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, and Huntington's disease predominantly pose a significant socioeconomic burden. Characterized by progressive neural dysfunction coupled with motor or intellectual impairment, the pathogenesis of ND may result from contributions of certain environmental and molecular factors. One such condition is hypoxia, characterized by reduced organ/tissue exposure to oxygen. Reduced oxygen supply often occurs during the pathogenesis of ND and the aging process. Despite the well-established relationship between these two conditions (i.e., hypoxia and ND), the underlying molecular events or mechanisms connecting hypoxia to ND remain ill-defined. However, the relatedness may stem from the protective or deleterious effects of the transcription factor, hypoxia-inducible factor 1-alpha (HIF-1α). The upregulation of HIF-1α occurs in the pathogenesis of most NDs. The dual function of HIF-1α in acting as a "killer factor" or a "protective factor" depends on the prevailing local cellular condition. The kynurenine pathway is a metabolic pathway involved in the oxidative breakdown of tryptophan. It is essential in neurotransmission and immune function and, like hypoxia, associated with ND. Thus, a good understanding of factors, including hypoxia (i.e., the biochemical implication of HIF-1α) and kynurenine pathway activation in NDs, focusing on Alzheimer's disease could prove beneficial to new therapeutic approaches for this disease, thus the aim of this review.


Assuntos
Doença de Alzheimer/patologia , Hipóxia/fisiopatologia , Cinurenina/metabolismo , Redes e Vias Metabólicas , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Humanos
8.
Anticancer Agents Med Chem ; 21(2): 162-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32723261

RESUMO

BACKGROUND: Cutaneous malignancies most commonly arise from skin epidermal cells. These cancers may rapidly progress from benign to a metastatic phase. Surgical resection represents the gold standard therapeutic treatment of non-metastatic skin cancer while chemo- and/or radiotherapy are often used against metastatic tumors. However, these therapeutic treatments are limited by the development of resistance and toxic side effects, resulting from the passive accumulation of cytotoxic drugs within healthy cells. OBJECTIVE: This review aims to elucidate how the use of monoclonal Antibodies (mAbs) targeting specific Tumor Associated Antigens (TAAs) is paving the way to improved treatment. These mAbs are used as therapeutic or diagnostic carriers that can specifically deliver cytotoxic molecules, fluorophores or radiolabels to cancer cells that overexpress specific target antigens. RESULTS: mAbs raised against TAAs are widely in use for e.g. differential diagnosis, prognosis and therapy of skin cancers. Antibody-Drug Conjugates (ADCs) particularly show remarkable potential. The safest ADCs reported to date use non-toxic photo-activatable Photosensitizers (PSs), allowing targeted Photodynamic Therapy (PDT) resulting in targeted delivery of PS into cancer cells and selective killing after light activation without harming the normal cell population. The use of near-infrared-emitting PSs enables both diagnostic and therapeutic applications upon light activation at the specific wavelengths. CONCLUSION: Antibody-based approaches are presenting an array of opportunities to complement and improve current methods employed for skin cancer diagnosis and treatment.


Assuntos
Antígenos de Neoplasias/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Imunoconjugados/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antígenos de Neoplasias/análise , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/farmacologia , Terapia de Alvo Molecular , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Prognóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/imunologia
9.
FASEB J ; 34(11): 14083-14092, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32885502

RESUMO

Cannabidiol (CBD) is considered a non-psychoactive, antioxidant, and anti-inflammatory compound derived from the Cannabis sativa plant. There are various reports on the versatile function of CBD, including ameliorating chronic inflammation and fibrosis formation in several tissue types. However, only a hand full of studies have proposed or provided a molecular justification for the beneficial properties of this Phyto-compound. This review focused on the anti-inflammation and anti-fibrotic effects of CBD based on modulating the associated chemokines/cytokines and receptor-mediated pathways. We also highlighted the regulatory impact of CBD on reactive oxygen species (ROS) producing-NADPH oxidase (Nox), and ROS scavenging-superoxide dismutase (SOD) enzymes. Although CBD has a low affinity to Cannabinoid receptors 1 and 2 (CB1 and CB2 ), we reported on the activation of these receptors by other CBD analogs, and CBD on non-CBD receptors. CBD downregulates pro-inflammatory and pro-fibrotic chemokines/cytokines by acting as direct or indirect agonists of Adenosine A2A /equilibrative nucleoside transporter receptors, Peroxisome proliferator-activated receptor gamma, and Transient receptor potential vanilloid receptors or channels, and as an antagonist of GPR55 receptors. CBD also caused the reduction and enhancement of the ROS producing, Nox and ROS-scavenging, SOD enzyme activities, respectively. This review thus recommends the continued study of CBD's molecular mechanism in treating established and emerging inflammatory and fibrosis-related diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Anticonvulsivantes/farmacologia , Canabidiol/farmacologia , Fibrose/tratamento farmacológico , Inflamação/tratamento farmacológico , Canais Iônicos/metabolismo , Animais , Fibrose/patologia , Humanos , Inflamação/patologia
10.
Molecules ; 25(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731629

RESUMO

The aim of this study was to explore the inhibitory potential of apoferritin or apoferritin-capped metal nanoparticles (silver, gold and platinum) against Trypanosomabrucei arginine kinase. The arginine kinase activity was determined in the presence and absence of apoferritin or apoferritin-capped metal nanoparticles. In addition, kinetic parameters and relative inhibition of enzyme activity were estimated. Apoferritin or apoferritin-capped metal nanoparticles' interaction with arginine kinase of T. brucei led to a >70% reduction in the enzyme activity. Further analysis to determine kinetic parameters suggests a mixed inhibition by apoferritin or apoferritin-nanoparticles, with a decrease in Vmax. Furthermore, the Km of the enzyme increased for both ATP and L-arginine substrates. Meantime, the inhibition constant (Ki) values for the apoferritin and apoferritin-nanoparticle interaction were in the submicromolar concentration ranging between 0.062 to 0.168 nM and 0.001 to 0.057 nM, respectively, for both substrates (i.e., L-arginine and ATP). Further kinetic analyses are warranted to aid the development of these nanoparticles as selective therapeutics. Also, more studies are required to elucidate the binding properties of these nanoparticles to arginine kinase of T. brucei.


Assuntos
Apoferritinas , Arginina Quinase , Nanopartículas Metálicas , Proteínas de Protozoários , Tripanossomicidas , Trypanosoma brucei brucei/enzimologia , Apoferritinas/química , Apoferritinas/farmacologia , Arginina Quinase/antagonistas & inibidores , Arginina Quinase/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , Tripanossomicidas/química , Tripanossomicidas/farmacologia
11.
J Proteomics ; 226: 103892, 2020 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629194

RESUMO

Differences in the physiological proteome of men of different racial origin is poorly researched, albeit hair is mostly composed of keratins and keratin-associated proteins. Hence, we have carried out label-free, shotgun proteomics analysis on hair samples collected from black African, Caucasian, Asian, and Mixed-Ancestry donors within a heterogeneous population of the Western Cape of South Africa. Further, the same hair was also classified using geometrical measurements. Using both qualitative and quantitative proteomics bioinformatics pipelines, we identified over 450 protein groups (FDR = 0.01). Identified protein classes included keratins, keratin-associated proteins, histone proteins and desmosomes, inter alia. No protein by quantitative proteomic analyses significantly differentiated racial or geometric groups in our cohort. Functional pathway analysis of top-ranking proteins showed enrichment for skin, epidermal and tissue development, as well as intermediate-filament organization. Racial classification is a social construct, and attributing differences in a biologic endpoint to it is both imprecise and valueless in the era of precision medicine. Nonetheless, clarity on the physiological hair proteome could serve as a foundation for using hair proteomics for disease biomarker and targeted therapy identification for precision medicine. For the first time, we established the physiological hair proteome of individuals in a culturally diverse cohort from Africa. SIGNIFICANCE: For the first time we have been able to characterize the physiological human hair proteome in a culturally diverse South African cohort. We have also identified that proteomics differences were not observed in individual hair samples using our quantitative proteomics bioinformatics pipeline. This outcome supports a widely known notion that DNA sequence comparison often shows that people on each continent are not more genetically similar to one another than to people who come from other continents and that there is more genetic variation in Africa. Hence, adaptive traits such as hair and skin phenotype are not scientifically valid distinctions. Racial classification is believed to be a social construct, and attributing differences in a biologic endpoint to it is both imprecise and valueless in the era of precision medicine. Our preliminary finding would serve as a much-needed foundation for establishing a well-annotated, customized hair proteomics repository for Africans.


Assuntos
Proteoma , Proteômica , Cabelo , Humanos , Masculino , Couro Cabeludo , África do Sul
12.
Biochem J ; 476(10): 1553-1570, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31072910

RESUMO

Angiotensin-converting enzyme (ACE) is a zinc metalloprotease best known for its role in blood pressure regulation. ACE consists of two homologous catalytic domains, the N- and C-domain, that display distinct but overlapping catalytic functions in vivo owing to subtle differences in substrate specificity. While current generation ACE inhibitors target both ACE domains, domain-selective ACE inhibitors may be clinically advantageous, either reducing side effects or having utility in new indications. Here, we used site-directed mutagenesis, an ACE chimera and X-ray crystallography to unveil the molecular basis for C-domain-selective ACE inhibition by the bradykinin-potentiating peptide b (BPPb), naturally present in Brazilian pit viper venom. We present the BPPb N-domain structure in comparison with the previously reported BPPb C-domain structure and highlight key differences in peptide interactions with the S4 to S9 subsites. This suggests the involvement of these subsites in conferring C-domain-selective BPPb binding, in agreement with the mutagenesis results where unique residues governing differences in active site exposure, lid structure and dynamics between the two domains were the major drivers for C-domain-selective BPPb binding. Mere disruption of BPPb interactions with unique S2 and S4 subsite residues, which synergistically assist in BPPb binding, was insufficient to abolish C-domain selectivity. The combination of unique S9-S4 and S2' subsite C-domain residues was required for the favourable entry, orientation and thus, selective binding of the peptide. This emphasizes the need to consider factors other than direct protein-inhibitor interactions to guide the design of domain-selective ACE inhibitors, especially in the case of larger peptides.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Oligopeptídeos/química , Peptidil Dipeptidase A/química , Animais , Células CHO , Catálise , Cricetulus , Cristalografia por Raios X , Humanos , Mutagênese Sítio-Dirigida , Peptidil Dipeptidase A/genética , Domínios Proteicos
13.
Proteomics Clin Appl ; 12(2)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28960873

RESUMO

The use of noninvasive human substrates to interrogate pathophysiological conditions has become essential in the post- Human Genome Project era. Due to its high turnover rate, and its long term capability to incorporate exogenous and endogenous substances from the circulation, hair testing is emerging as a key player in monitoring long term drug compliance, chronic alcohol abuse, forensic toxicology, and biomarker discovery, among other things. Novel high-throughput 'omics based approaches like proteomics have been underutilized globally in comprehending human hair morphology and its evolving use as a diagnostic testing substrate in the era of precision medicine. There is paucity of scientific evidence that evaluates the difference in drug incorporation into hair based on lipid content, and very few studies have addressed hair growth rates, hair forms, and the biological consequences of hair grooming or bleaching. It is apparent that protein-based identification using the human hair proteome would play a major role in understanding these parameters akin to DNA single nucleotide polymorphism profiling, up to single amino acid polymorphism resolution. Hence, this work seeks to identify and discuss the progress made thus far in the field of molecular hair testing using proteomic approaches, and identify ways in which proteomics would improve the field of hair research, considering that the human hair is mostly composed of proteins. Gaps in hair proteomics research are identified and the potential of hair proteomics in establishing a historic medical repository of normal and disease-specific proteome is also discussed.


Assuntos
Diagnóstico , Cabelo/metabolismo , Proteômica/métodos , Terapêutica , Humanos , Espectrometria de Massas , Análise Serial de Proteínas
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