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1.
Int Immunol ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567483

RESUMO

Transforming growth factor-ß-activated kinase 1 (TAK1) plays a pivotal role in innate and adaptive immunity. TAK1 is essential for the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB pathways downstream of diverse immune receptors, including Toll-like receptors (TLRs). Upon stimulation with TLR ligands, TAK1 is activated via recruitment to lysine 63-linked polyubiquitin chain through TAK1-binding proteins (TAB) 2 and TAB3. However, the physiological importance of TAB2 and TAB3 in macrophages is still controversial. A previous study has shown that mouse bone marrow-derived macrophages (BMDMs) isolated from mice double deficient for TAB2 and TAB3 produced tumor necrosis factor (TNF)-α and interleukin (IL)-6 to the similar levels as control wild-type BMDMs in response to TLR ligands such as lipopolysaccharide (LPS) or Pam3CSK4, indicating that TAB2 and TAB3 are dispensable for TLR signaling. In this study, we revisited the role of TAB2 and TAB3 using an improved mouse model. We observed a significant impairment in the production of pro-inflammatory cytokines and chemokine in LPS- or Pam3CSK4-treated BMDMs deficient for both TAB2 and TAB3. Double deficiency of TAB2 and TAB3 resulted in the decreased activation of NF-κB and MAPK pathways as well as the slight decrease in TAK1 activation in response to LPS or Pam3CSK4. Notably, the TLR-mediated expression of inhibitor of NF-κB (IκB)ζ was severely compromised at the protein and mRNA levels in the TAB2/TAB3 double-deficient BMDMs, thereby impeding IL-6 production. Our results suggest that TAB2 and TAB3 play a redundant and indispensable role in TLR signaling pathway.

2.
Biochem Pharmacol ; 212: 115545, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37044296

RESUMO

Long-standing scarcity of efficacious treatments and tumor heterogeneity have contributed to triple-negative breast cancer (TNBC), a subtype with a poor prognosis and aggressive behavior that accounts for 10-15% of all new cases of breast cancer. TNBC is characterized by the absence of progesterone and estrogen receptor expression and lacks gene amplification or overexpression of HER2. Genomic sequencing has detected that the unique mutational profile of both the somatic and germline modifications in TNBC is staggeringly dissimilar from other breast tumor subtypes. The clinical utility of sequencing germline BRCA1/2 genes has been well established in TNBC. Nevertheless, reports regarding the penetrance and risk of other susceptibility genes are relatively scarce. Recurring mutations (e.g., TP53 and PI3KCA mutations) occur together with rare mutations in TNBC, and the shared effects of genomic modifications drive its progression. Given the heterogeneity and complexity of this disease, a clinical understanding of the genomic modifications in TNBC can pave an innovative way toward its therapy. In this review, we summarized the most recent discoveries associated with the underlying biology of developmental signaling pathways in TNBC. We also summarize the recent advancements in genetics and epidemiology and discuss state-of-the-art vaccine-based therapeutic strategies for TNBC that will enable tailored therapeutics.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Proteína BRCA1/genética , Epidemiologia Molecular , Proteína BRCA2/genética , Recidiva Local de Neoplasia
3.
Clin Exp Pharmacol Physiol ; 50(3): 205-217, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36479862

RESUMO

Many research studies have proposed that about two-thirds of the medicinal plant species of the world possess significant antioxidant potential. Antioxidants are very beneficial as they decrease oxidative stress (OS) in cells and hence play their role in management as well as treatment of numerous diseases like cancers, cardiovascular diseases, as well as many inflammatory illnesses. This review comprises the antioxidant potential of numerous parts of medicinal plants like leaves, stems, roots, seeds, fruits, as well as bark. Synthetic antioxidants named butylated hydroxyanisole (BHA) as well as butylated hydroxytoluene (BHT) are extensively employed in foods because of their role as food preservatives. Several natural antioxidants have better efficacy as compared to synthetic antioxidants. These medicinal plants include Geranium sanguineum L., Rheum ribes L., Diospyros abyssinica, Sargentodoxa cuneata Rehd. Et Wils, Pistacia lentiscus, Ficus microcarpa L. fil., Polyalthia cerasoides (Roxb.) Bedd, Cunn, Teucrium polium L., Crataeva nurvala Buch-Ham., Urtica dioica L., Dracocephalum moldavica L., Momordica Charantia L., Acacia auriculiformis A., Bidens pilosa Linn. The Lamiaceae species, Radiata, Leea indica, Pelargonium endlicherianum, Salvia officinalis L., and Uncaria tomentosa (Willd.) DC. The literature study disclosed more side effects of synthetic antioxidants (including food additives) in comparison with natural antioxidants and for prevention of many diseases.


Assuntos
Antioxidantes , Plantas Medicinais , Antioxidantes/farmacologia , Hidroxitolueno Butilado/efeitos adversos , Hidroxianisol Butilado/efeitos adversos
4.
Pharm Pract (Granada) ; 20(2): 2647, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35919803

RESUMO

Aim of present study was to assess pharmacological (antioxidant, antibacterial & antifungal) potential of Operculina terpathum seeds. Ethanolic extract was prepared and its phytochemical evaluation show the different chemical compounds such as carbohydrates, phenols, tannin, flavonoids, cardiac glycosides, steroids, alkaloids and proteins. FTIR spectra showed the presence of organic acids, hydroxyl and phenolic compounds, amino groups, aliphatic compounds, functional groups such as amide, ketone, aldehyde, aromatics and halogen compounds. Antioxidant activity of the Operculina terpathum alcoholic extract was performed by DPPH method and it showed 97.13%whereas IC50±SEM (µg/ml) was 1.425±0.16. Antibacterial activity was performed against different bacterial strains and results were comparable with that of standard. Maximum antibacterial activity was exhibited by Bacillus subtillis (28.33±2 mm) and Bacillus pumilus (25.33±2 mm) respectively. Antifungal activity was also performed and it showed maximum activity against Aspergillus flavous and Candida albicans6±1, 5±1mm respectively. These results showed that Operculina terpathum has good antibacterial and antifungal activity against different microbes and it could be used as an alternative to antibiotics, as the antibiotics resistance is very common now a days.

5.
Rev Diabet Stud ; 18(2): 93-99, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35831936

RESUMO

Cholistan Desert is a sandy desert located in southern Punjab, Pakistan. The area is rich in more than 64 medicinal plants among 138 plant species. It is noteworthy that this remote desert lacks modern health care facilities and its inhabitants are dependent on locally-available plant species for the treatment of acute and chronic illnesses. Medicinal plants, traditionally have been ideal sources of remedies for the management of many non-communicable diseases; most modern prescriptions drugs have their origins from plants. Diabetes is increasing at an alarming rate in the past few decades. Whereas medicinal plants are used globally, the specific properties of only a few have been identifies scientifically. Similarly, little scientific evidence exists that confirms the efficacy of the medicinal plants of this region for diabetes management. Ethnobotanical studies show that locally-available medicinal plants do have anti-diabetic potential. We reviewed the medicinal properties of 36 of these plants. Several ingredients derived from these plants have chemical constituents that demonstrate anti-diabetic activity, thereby validating their importance for the management of diabetes.


Assuntos
Diabetes Mellitus , Plantas Medicinais , Diabetes Mellitus/tratamento farmacológico , Etnobotânica , Humanos , Paquistão , Fitoterapia
6.
Anaerobe ; 73: 102499, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890812

RESUMO

BACKGROUND AND OBJECTIVES: Clostridium perfringens is a causative agent of enteric infections in animals including poultry by producing twenty different types of toxins. A single strain produces only a subset of these toxins, which form the basis of its classification into seven toxinotypes (A-G). C. perfringens toxinotype A is a widespread cause of necrotic enteritis (NE) in poultry. The current study was conducted to determine the prevalence of different toxins and antimicrobial susceptibility of C. perfringens isolated from Pakistan NE affected poultry. METHODS: A total of 134 intestinal samples of the diseased birds were collected postmortem and processed for isolation of C. perfringens using tryptose sulphite cycloserine (TSC) agar supplemented with d-cycloserine. Isolates were confirmed by Gram's staining, biochemical and molecular analyses. Toxinotyping was performed by multiplex PCR. Antimicrobial susceptibility profile of isolates was performed by Kirby Bauer disc diffusion method. RESULTS: A total of 34 strains of C. perfringens were isolated from 134 samples with prevalence rate of 25.37%. All the isolated strains were toxinotype A, as they were positive for alpha toxin (CPA) and negative for other tested toxins such as beta (CPB), epsilon (ETX), iota (ITX), enterotoxin (CPE), toxin perfringens large (TpeL) and necrotic B-like toxin (NetB). Interestingly, all the isolated strains of C. perfringens were multidrug resistant. The highest resistance was observed against Neomycin, Trimethoprim, Tetracycline and Lincomycin which are routinely used at Pakistan poultry production. CONCLUSION: C. perfringens toxinotype A is prevalent in Pakistan poultry. Incidence of C. perfringens with prevalence rate of 25.37% can pose serious threat to Pakistan's poultry industry given that all the isolated strains were multidrug resistant. Our findings highlight the need for new antibiotics and antibiotic alternatives to overcome multidrug resistance.


Assuntos
Toxinas Bacterianas , Infecções por Clostridium , Enterite , Doenças das Aves Domésticas , Animais , Antibacterianos/farmacologia , Toxinas Bacterianas/análise , Toxinas Bacterianas/genética , Galinhas , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/genética , Enterite/veterinária , Enterotoxinas/genética , Paquistão , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia
7.
Front Pharmacol ; 12: 731828, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512357

RESUMO

To date, the current COVID-19 pandemic caused by SARS-CoV-2 has infected 99.2 million while killed 2.2 million people throughout the world and is still spreading widely. The unavailability of potential therapeutics against this virus urges to search and develop new drugs. SARS-CoV-2 enters human cells by interacting with human angiotensin-converting enzyme 2 (ACE2) receptor expressed on human cell surface through utilizing receptor-binding domain (RBD) of its spike glycoprotein. The RBD is highly conserved and is also a potential target for blocking its interaction with human cell surface receptor. We designed short peptides on the basis of our previously reported truncated ACE2 (tACE2) for increasing the binding affinity as well as the binding interaction network with RBD. These peptides can selectively bind to RBD with much higher affinities than the cell surface receptor. Thus, these can block all the binding residues required for binding to cell surface receptor. We used selected amino acid regions (21-40 and 65-75) of ACE2 as scaffold for the de novo peptide design. Our designed peptide Pep1 showed interactions with RBD covering almost all of its binding residues with significantly higher binding affinity (-13.2 kcal mol-1) than the cell surface receptor. The molecular dynamics (MD) simulation results showed that designed peptides form a stabilized complex with RBD. We suggest that blocking the RBD through de novo designed peptides can serve as a potential candidate for COVID-19 treatment after further clinical investigations.

8.
Pharmaceuticals (Basel) ; 14(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062812

RESUMO

ß-Lactam antibiotics target penicillin-binding proteins and inhibit the synthesis of peptidoglycan, a crucial step in cell wall biosynthesis. Staphylococcus aureus acquires resistance against ß-lactam antibiotics by producing a penicillin-binding protein 2a (PBP2a), encoded by the mecA gene. PBP2a participates in peptidoglycan biosynthesis and exhibits a poor affinity towards ß-lactam antibiotics. The current study was performed to determine the diversity and the role of missense mutations of PBP2a in the antibiotic resistance mechanism. The methicillin-resistant Staphylococcus aureus (MRSA) isolates from clinical samples were identified using phenotypic and genotypic techniques. The highest frequency (60%, 18 out of 30) of MRSA was observed in wound specimens. Sequence variation analysis of the mecA gene showed four amino acid substitutions (i.e., E239K, E239R, G246E, and E447K). The E239R mutation was found to be novel. The protein-ligand docking results showed that the E239R mutation in the allosteric site of PBP2a induces conformational changes in the active site and, thus, hinders its interaction with cefoxitin. Therefore, the present report indicates that mutation in the allosteric site of PBP2a provides a more closed active site conformation than wide-type PBP2a and then causes the high-level resistance to cefoxitin.

9.
PLoS Negl Trop Dis ; 15(5): e0009371, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33939717

RESUMO

BACKGROUND: Malaria, disproportionately affects poor people more than any other disease of public health concern in developing countries. In resource-constrained environments, monitoring the occurrence of malaria is essential for the success of national malaria control programs. Militancy and military conflicts have been a major challenge in monitoring the incidence and controlling malaria and other emerging infectious diseases. The conflicts and instability in Afghanistan have resulted in the migration of refugees into the war-torn tribal districts of Pakistan's Khyber Pakhtunkhwa (KPK) province and the possible introduction of many contagious epidemics. Although malaria is very common in all tribal districts, molecular, clinical and epidemiological data are scarce in these high-burden districts. Therefore, for the proper surveillance, detection, and control of malaria, obtaining and analyzing reliable data in these districts is essential. METHODOLOGY/PRINCIPAL FINDINGS: All 1,127 malaria-suspected patients were sampled within the transmission season in the tribal districts of KPK province between March 2016 to December 2018. After a detailed demographic and clinical investigation of malaria-suspected patients, the data were recorded. The data of the control group was collected simultaneously at the same site. They were considered as uncomplicated cases for statistical analyses. Blood samples were collected from malaria-suspected patients for the detection of Plasmodium species using microscopy and nested PCR (nPCR). Microscopy and nPCR examination detected 78% (n = 882) and 38% (n = 429) Plasmodium-positive patients, respectively. Among1,127 of 429nPCR detected cases with both species of malaria, the frequency of complications was as follows: anemia (n = 71; 16.5%), decompensated shock (n = 40; 9%), hyperpyrexia (n = 117; 27%), hyperparasitaemia (n = 49; 11%) hypoglycemia (n = 45; 10.5%), jaundice (n = 54; 13%), multiple convulsions (n = 37; 9%), and petechia (n = 16; 4%). We observed that 37% (n = 157 out of 429) of those patients infected by both Plasmodium species were children between the ages of 1 and 15 years old. The results revealed that Bajaur (24%), Kurram (20%), and Khyber (18%) districtshada higher proportion of P. vivax than P. falciparum cases. Most of the malaria cases were males (74%). Patients infected by both Plasmodium species tended to less commonly have received formal education and ownership of wealth indicators (e.g., fridge, TV set) was lower. CONCLUSIONS/SIGNIFICANCE: Malaria in tribal districts of the KPK province largely affects young males. P. vivax is a major contributor to the spread of malaria in the area, including severe malaria. We observed a high prevalence of P. vivax in the Bajaur district. Children were the susceptible population to malaria infections whereas they were the least expected to use satisfactory prevention strategies. A higher level of education, a possession of TV sets, the use of bed nets, the use of repellent fluids, and fridges were all associated with protection from malaria. An increased investment in socio-economic development, a strong health infrastructure, and malaria education are key interventions to reduce malaria in the tribal districts.


Assuntos
Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Conflitos Armados/estatística & dados numéricos , Estudos de Casos e Controles , Criança , Pré-Escolar , Indicadores de Doenças Crônicas , Feminino , Humanos , Lactente , Masculino , Paquistão/epidemiologia , Plasmodium falciparum/genética , Plasmodium vivax/genética , Reação em Cadeia da Polimerase , Refugiados/estatística & dados numéricos , Estudos Retrospectivos , Fatores Socioeconômicos , Adulto Jovem
10.
J Biomol Struct Dyn ; 39(10): 3605-3614, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32396773

RESUMO

The current pandemic of Covid-19 caused by SARS-CoV-2 is continued to spread globally and no potential drug or vaccine against it is available. Spike (S) glycoprotein is the structural protein of SARS-CoV-2 located on the envelope surface, involve in interaction with angiotensin converting enzyme 2 (ACE2), a cell surface receptor, followed by entry into the host cell. Thereby, blocking the S glycoprotein through potential inhibitor may interfere its interaction with ACE2 and impede its entry into the host cell. Here, we present a truncated version of human ACE2 (tACE2), comprising the N terminus region of the intact ACE2 from amino acid position 21-119, involved in binding with receptor binding domain (RBD) of SARS-CoV-2. We analyzed the in-silico potential of tACE2 to compete with intact ACE2 for binding with RBD. The protein-protein docking and molecular dynamic simulation showed that tACE2 has higher binding affinity for RBD and form more stabilized complex with RBD than the intact ACE2. Furthermore, prediction of tACE2 soluble expression in E. coli makes it a suitable candidate to be targeted for Covid-19 therapeutics. This is the first MD simulation based findings to provide a high affinity protein inhibitor for SARS-CoV-2 S glycoprotein, an important target for drug designing against this unprecedented challenge.Communicated by Ramaswamy H. Sarma.


Assuntos
Enzima de Conversão de Angiotensina 2/farmacologia , COVID-19 , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/química , Sítios de Ligação , COVID-19/terapia , Escherichia coli , Humanos , Simulação de Dinâmica Molecular , Ligação Proteica , SARS-CoV-2
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