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2.
Biochimie ; 196: 234-242, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35121053

RESUMEN

The study investigated the influence of friedelin, resinone, tingenone and betulin plant-based secondary metabolite compounds on cellular proliferation, extracellular matrix (ECM) components synthesis, expression of chondrogenic markers and maturation of differentiated chondrocytes (cell proliferation and hypertrophy) in porcine adipose-derived mesenchymal stem cells (pADMSCs) undergoing chondrogenic differentiation. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and Cyquant assays were used to determine cell proliferation, viability, and total cellular DNA, DMMB (Dimethyl methylene blue) was used for glycosaminoglycan (GAG) synthesis, RT-qPCR for gene expression and histology combined with immunohistochemistry for cartilage ECM proteoglycan deposition. The MTT results showed that friedelin at 37 µM, resinone at 36 µM and betulin at 18 µM with cell viability of above 100% compared to control. Tingenone at 37 µM showed cell viability of about 76%. These concentrations were considered the most effective with no toxicity effect on the cells and were further analysed with TGF-ß3 (10 ng/mL) as a positive control. The results showed a high synthesis of DNA with friedelin on day 14. There was up-regulation of SOX 9, Col II and Col X with friedelin and resinone at day 14 with the significance of p < 0.01. Pellet from friedelin, resinone and tingenone showed more staining of the matrix for Safranin-O and Toluidine blue at day 14. Immunohistostaining of collagen type X (COL-10) showed more stain intensity at friedelin and resinone on day 21. These results provided new knowledge on the potential use of natural isolated secondary metabolites compounds as inducers for chondrogenic and bone differentiation.


Asunto(s)
Condrogénesis , Células Madre Mesenquimatosas , Animales , Diferenciación Celular , Células Cultivadas , Condrocitos/metabolismo , Condrogénesis/genética , Colágeno Tipo II/genética , ADN/metabolismo , Células Madre Mesenquimatosas/metabolismo , Porcinos , Triterpenos
3.
Tissue Eng Part A ; 28(3-4): 136-149, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34269614

RESUMEN

Eucomis autumnalis subsp. autumnalis (Mill.) Chitt. (EASA) is a commonly used medicinal plant for the treatment of fractures, osteoarthritis, back pain, and wound healing in Southern Africa. In this study, the effects of water and acetone extracts of EASA on the viability, osteogenic differentiation, and mineralization of human adipose-derived stem cells (hADSCs) were investigated in vitro. The results showed that both water and acetone extracts of EASA increased cell viability at concentrations between 10 and 50 µg/mL on day 7 and 14 of treatment. Osteogenic differentiation and mineralization of hADSCs were optimal at 5 µg/mL for the water extract and at 5-10 µg/mL for the acetone extract. A 5 µg/mL acetone extract upregulated the expression of the ALP, Runx2, Col1a1, and osteopontin genes. In addition, EASA upregulated ß-catenin, cyclin D1, and osteoprotegerin (OPG). The results suggest that EASA may likely upregulate the expression of ß-catenin, which subsequently upregulates the osteogenic marker genes through Runx2. However, EASA also upregulates cyclin D1 supporting the growth of precursor cells. Additionally, EASA upregulated the expression of OPG suggesting that it may inhibit bone resorption. The results of this study support the traditional use of the plant in bone healing. Impact statement Herbal remedies are used to treat various ailments by almost 80% of the developing world. Eucomis autumnalis is one of the most used medicinal plants in Southern Africa for the treatment of backache, osteoarthritis, and healing of fracture. There is a scarcity of scientific evidence to prove the efficacy of E. autumnalis for fracture repair. This study sought to assess the effect of the crude extracts in vitro and found that E. autumnalis promoted viability and osteogenic differentiation of human adipose-derived stem cells as demonstrated by biochemical and genetic markers. This medicinal plant could therefore have potential to regenerate bone tissue.


Asunto(s)
Osteogénesis , Células Madre , Adipocitos , Tejido Adiposo , Diferenciación Celular , Células Cultivadas , Humanos
4.
BMC Infect Dis ; 21(1): 719, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34332551

RESUMEN

BACKGROUND: COVID-19 has affected almost every country in the world, especially in terms of health system capacity and economic burden. People from sub-Saharan Africa (SSA) often face interaction between human immunodeficiency virus (HIV) infection and non-communicable diseases such as cardiovascular disease. Role of HIV infection and anti-retroviral treatment (ART) in altered cardiovascular risk is questionable and there is still need to further carry out research in this field. However, thus far it is unclear, what impact the COVID-19 co-infection in people living with HIV (PLHIV), with or without therapy will have. The ENDOCOVID project aims to investigate whether and how HIV-infection in COVID-19 patients modulates the time course of the disease, alters cardiovascular risk, and changes vascular endothelial function and coagulation parameters/ thrombosis risk. METHODS: A total of 1026 patients will be included into this study. Cardiovascular research PLHIV with (n = 114 in each of the three recruiting centers) - or without - ART (n = 114 in each of the three recruiting centers) with COVID-19 and HIV-negative with COVID-19 (n = 114 in each of the three recruiting centers) will be carried out via clinical and biochemical measurements for cardiovascular risk factors and biomarkers of cardiovascular disease (CVD). Vascular and endothelial function will be measured by brachial artery flow-mediated dilatation (FMD), carotid intima-media thickness (IMT) assessments, and retinal blood vessel analyses, along with vascular endothelial biomarkers and cogualation markers. The correlation between HIV-infection in COVID-19 PLHIV with or without ART and its role in enhancement of cardiovascular risk and endothelial dysfunction will be assessed at admission, weekly, at discharge and, 4 weeks post-discharge (if possible). IMPACT OF PROJECT: The ENDOCOVID project aims to evaluate in the long-term the cardiovascular risk and vascular endothelial function in PLHIV thus revealing an important transitional cardiovascular phenotype in COVID-19. The study was registered under clinicaltrials.gov (NCT04709302).


Asunto(s)
COVID-19 , Enfermedades Cardiovasculares , Infecciones por VIH , Trombosis , Cuidados Posteriores , Enfermedades Cardiovasculares/epidemiología , Grosor Intima-Media Carotídeo , Endotelio Vascular , Infecciones por VIH/complicaciones , Humanos , Alta del Paciente , Factores de Riesgo , SARS-CoV-2
5.
J Water Health ; 18(4): 494-504, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32833676

RESUMEN

Solar disinfection (SODIS) has been shown to reduce the risk associated with the contraction of water borne diseases such as cholera. However, little or no research has been undertaken in exploring the role played by the immune system following the consumption of solar inactivated water pathogens. This study investigated the potential for solar inactivated Vibrio cholerae to induce the maturation of dendritic cells in vitro. Dendritic cells are professional antigen presenting cells found in mammals. However, only in their mature form are dendritic cells able to play their role towards a long lasting immune response. Three strains of V. cholerae were solar irradiated for 7 hours. Thereafter, the solar irradiated, non-solar irradiated, phosphate buffered saline prepared and heat/chemically inactivated cultures of V. cholerae as well as lipopolysaccharide and cholerae toxin-ß subunit were used to stimulate immature dendritic cells. After 48 hours, the dendritic cells were assessed for the expression of CD54, CD80, CD83, CD86, MHC-I and MHC-II cell surface markers. Results show that solar inactivated V. cholerae was able to induce maturation of the dendritic cells in vitro. These findings suggest that there may be an immunological benefit in consuming SODIS treated water.


Asunto(s)
Cólera , Células Dendríticas , Luz Solar , Vibrio cholerae , Animales , Anticuerpos Antibacterianos , Línea Celular
6.
Front Pharmacol ; 11: 600364, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33833677

RESUMEN

Background: End-stage-renal-failure (ESRF) patients attending clustered out-patient dialysis are susceptible to SARS-CoV-2 infection. Comorbidities render them vulnerable to severe COVID-19. Although preventative and mitigation strategies are recommended, the effect of these are unknown. A period of "potential-high-infectivity" results if a health-care-worker (HCWs) or a patient becomes infected. Aim: We describe and analyze early, universal SARS-CoV-2 real time reverse transcription polymerase chain reaction (RT-PCR) tests, biomarker monitoring and SARS-CoV-2 preventative strategies, in a single dialysis center, after a positive patient was identified. Methodology: The setting was a single outpatient dialysis center in Johannesburg, South Africa which had already implemented preventative strategies. We describe the management of 57 patients and 11 HCWs, after one of the patients tested positive for SARS-CoV-2. All individuals were subjected to RT-PCR tests and biomarkers (Neutrophil-Lymphocyte Ratio, C-reactive protein, and D-Dimer) within 72 h (initial-tests). Individuals with initial negative RT-PCR and abnormal biomarkers (one or more) were subjected to repeat RT-PCR and biomarkers (retest subgroup) during the second week. Additional stringent measures (awareness of viral transmission, dialysis distancing and screening) were implemented during the period of "potential high infectivity." The patient retest subgroup also underwent clustered dialysis until retest results became available. Results: A second positive-patient was identified as a result of early universal RT-PCR tests. In the two positive-patients, biomarker improvement coincided with RT-PCR negative tests. We identified 13 individuals for retesting. None of these retested individuals tested positive for SARS-CoV-2 and there was no deterioration in median biomarker values between initial and retests. Collectively, none of the negative individuals developed COVID-19 symptoms during the period "potential high infectivity." Conclusion: A SARS-CoV-2 outbreak may necessitate additional proactive steps to counteract spread of infection. This includes early universal RT-PCR testing and creating further awareness of the risk of transmission and modifying preventative strategies. Abnormal biomarkers may be poorly predictive of SARS-CoV-2 infection in ESRF patients due to underlying illnesses. Observing dynamic changes in biomarkers in RT-PCR positive and negative-patients may provide insights into general state of health.

7.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31540457

RESUMEN

The promise of regenerative medicine and tissue engineering is founded on the ability to regenerate diseased or damaged tissues and organs into functional tissues and organs or the creation of new tissues and organs altogether. In theory, damaged and diseased tissues and organs can be regenerated or created using different configurations and combinations of extracellular matrix (ECM), cells, and inductive biomolecules. Regenerative medicine and tissue engineering can allow the improvement of patients' quality of life through availing novel treatment options. The coupling of regenerative medicine and tissue engineering with 3D printing, big data, and computational algorithms is revolutionizing the treatment of patients in a huge way. 3D bioprinting allows the proper placement of cells and ECMs, allowing the recapitulation of native microenvironments of tissues and organs. 3D bioprinting utilizes different bioinks made up of different formulations of ECM/biomaterials, biomolecules, and even cells. The choice of the bioink used during 3D bioprinting is very important as properties such as printability, compatibility, and physical strength influence the final construct printed. The extracellular matrix (ECM) provides both physical and mechanical microenvironment needed by cells to survive and proliferate. Decellularized ECM bioink contains biochemical cues from the original native ECM and also the right proportions of ECM proteins. Different techniques and characterization methods are used to derive bioinks from several tissues and organs and to evaluate their quality. This review discusses the uses of decellularized ECM bioinks and argues that they represent the most biomimetic bioinks available. In addition, we briefly discuss some polymer-based bioinks utilized in 3D bioprinting.


Asunto(s)
Bioimpresión/métodos , Matriz Extracelular/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Materiales Biocompatibles/química , Humanos , Polímeros/química , Impresión Tridimensional , Medicina Regenerativa/métodos
8.
Tissue Eng Part A ; 25(11-12): 827-829, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30838937

RESUMEN

IMPACT STATEMENT: Medicinal plants are used by various traditional healers to alleviate the signs and symptoms associated with numerous diseases such as osteoarthritis, asthma, cancer, heart disease, tuberculosis, swollen ankles, bone fracture, malaria, convulsion, piles, hypertension, typhoid fever, diabetes, and anemia. Our research is relevant to communities that rely solely on traditional medicine for their well-being.


Asunto(s)
Plantas Medicinales , Medicina Regenerativa/métodos , Medicina Regenerativa/tendencias , Ingeniería de Tejidos/métodos , Ingeniería de Tejidos/tendencias , África , Humanos
9.
Tissue Eng Part A ; 25(15-16): 1137-1145, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30511903

RESUMEN

IMPACT STATEMENT: Eucomis autumnalis is one plant that is used by various traditional healers to alleviate the signs and symptoms associated with osteoarthritis. Although the exact mechanisms remain unknown, we hypothesized that this plant can induce chondrogenesis. In this work, we explored the potential for an aqueous crude extract from E. autumnalis to induce chondrogenesis in porcine adipose-derived mesenchymal stem cells (MSCs). The results reported in our article indicate that the aqueous crude extract from E. autumnalis was able to indeed induce chondrogenesis. Our research is relevant to communities that rely on plant-based remedies for their well-being.


Asunto(s)
Tejido Adiposo/citología , Asparagaceae/química , Condrogénesis , Células Madre Mesenquimatosas/citología , Extractos Vegetales/farmacología , Agua/química , Animales , Biomarcadores/metabolismo , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Forma de la Célula/efectos de los fármacos , Condrogénesis/efectos de los fármacos , Sulfatos de Condroitina/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Reproducibilidad de los Resultados , Porcinos
10.
Stem Cells Int ; 2018: 2495848, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30154861

RESUMEN

Humans and animals lose tissues and organs due to congenital defects, trauma, and diseases. The human body has a low regenerative potential as opposed to the urodele amphibians commonly referred to as salamanders. Globally, millions of people would benefit immensely if tissues and organs can be replaced on demand. Traditionally, transplantation of intact tissues and organs has been the bedrock to replace damaged and diseased parts of the body. The sole reliance on transplantation has created a waiting list of people requiring donated tissues and organs, and generally, supply cannot meet the demand. The total cost to society in terms of caring for patients with failing organs and debilitating diseases is enormous. Scientists and clinicians, motivated by the need to develop safe and reliable sources of tissues and organs, have been improving therapies and technologies that can regenerate tissues and in some cases create new tissues altogether. Tissue engineering and/or regenerative medicine are fields of life science employing both engineering and biological principles to create new tissues and organs and to promote the regeneration of damaged or diseased tissues and organs. Major advances and innovations are being made in the fields of tissue engineering and regenerative medicine and have a huge impact on three-dimensional bioprinting (3D bioprinting) of tissues and organs. 3D bioprinting holds great promise for artificial tissue and organ bioprinting, thereby revolutionizing the field of regenerative medicine. This review discusses how recent advances in the field of regenerative medicine and tissue engineering can improve 3D bioprinting and vice versa. Several challenges must be overcome in the application of 3D bioprinting before this disruptive technology is widely used to create organotypic constructs for regenerative medicine.

11.
Sci Rep ; 8(1): 5318, 2018 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-29593232

RESUMEN

Homeostasis of osteoclast formation from bone marrow macrophages (BMM) is regulated by paracrine signals of the neighbourhood bone cells particularly mesenchymal stem cells (MSC), osteoblasts and osteocytes (OC). Besides paracrine cues, collagen and glycosaminoglycan are involved in controlling bone homeostasis. Towards this approach, different molecular weight collagens were reacted with MSC, OC and BMM to understand the bone homeostasis activity of collagen. The up-regulating effect of collagens on osteogenic cell growth was confirmed by the presence of mineralized nodules in the osteoblastogenic lineage cells and increased osteogenic stimulatory gene expression. The decreased BMM-derived TRAP+ osteoclasts number and osteoclastogenic regulatory gene expression of OC could demonstrate the exploitive osteoclastogenic activity of collagens. Osteoclastogenesis from BMM was triggered by paracrine cues of OC in some extend, but it was down-regulated by collagen. Overall, the effect of collagen on osteoclastogenesis and osteoblastogenesis may depend on the molecular weight of collagens, and collagen suppresses osteoclastogenesis, at least in part by downregulating the secretion of cytokines in OC.


Asunto(s)
Comunicación Celular , Colágeno/metabolismo , Macrófagos/metabolismo , Osteocitos/metabolismo , Osteogénesis , Animales , Biomarcadores , Comunicación Celular/efectos de los fármacos , Técnicas de Cultivo de Célula , Diferenciación Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Técnicas de Cocultivo , Colágeno/administración & dosificación , Macrófagos/efectos de los fármacos , Células Madre Mesenquimatosas , Ratones , Osteoblastos , Osteoclastos , Osteocitos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo
13.
PLoS One ; 10(6): e0130190, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26066787

RESUMEN

The use of solar irradiation to sterilize water prior to its consumption has resulted in the reduction of water related illnesses in waterborne disease endemic communities worldwide. Currently, research on solar water disinfection (SODIS) has been directed towards understanding the underlying mechanisms through which solar irradiation inactivates the culturability of microorganisms in water, enhancement of the disinfection process, and the health impact of SODIS water consumption. However, the immunological consequences of SODIS water consumption have not been explored. In this study, we investigated the effect that solar irradiated V. cholerae may have had on the secretion of cytokines and chemokines by the JAWS II dendritic cell line in vitro. The JAWS II dendritic cell line was stimulated with the different strains of V. cholerae that had been: (i) prepared in PBS, (ii) inactivated through a combination of heat and chemical, (iii) solar irradiated, and (iv) non-solar irradiated, in bottled water. As controls, LPS (1 µg/ml) and CTB (1 µg/ml) were used as stimulants. After 48 hours of stimulation the tissue culture media from each treatment was qualitatively and quantitatively analysed for the presence of IL-1α, IL-1ß, IL-6, IL-7, IL-10, IL-12p40, IL-12p70, IL-15, MIP-1α, MIP-1ß, MIP-2, RANTES, TNF-α, IL-23 and IL-27. Results showed that solar irradiated cultures of V. cholerae induced dendritic cells to secrete significant (p<0.05) levels of pro-inflammatory cytokines in comparison to the unstimulated dendritic cells. Furthermore, the amount of pro-inflammatory cytokines secreted by the dendritic cells in response to solar irradiated cultures of V. cholerae was not as high as observed in treatments involving non-solar irradiated cultures of V. cholerae or LPS. Our results suggest that solar irradiated microorganisms are capable of inducing the secretion of pro-inflammatory cytokines and chemokines. This novel finding is key towards understanding the possible immunological consequences of consuming SODIS treated water.


Asunto(s)
Quimiocinas/metabolismo , Citocinas/metabolismo , Células Dendríticas/metabolismo , Inflamación/patología , Energía Solar , Luz Solar , Vibrio cholerae/inmunología , Animales , Células Cultivadas , Quimiocinas/efectos de la radiación , Cólera/complicaciones , Cólera/inmunología , Cólera/metabolismo , Cólera/microbiología , Citocinas/efectos de la radiación , Células Dendríticas/citología , Células Dendríticas/microbiología , Células Dendríticas/efectos de la radiación , Desinfección/métodos , Ensayo de Inmunoadsorción Enzimática , Humanos , Técnicas In Vitro , Inflamación/etiología , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína p53 Supresora de Tumor/fisiología , Vibrio cholerae/crecimiento & desarrollo , Vibrio cholerae/efectos de la radiación
14.
J Water Health ; 12(3): 393-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25252341

RESUMEN

Cholera remains a problem in developing countries. This is attributed to the unavailability of proper water treatment, sanitary infrastructure and poor hygiene. As a consequence, countries facing cholera outbreaks rely on interventions such as the use of oral rehydration therapy and antibiotics to save lives. In addition to vaccination, the provision of chlorine tablets and hygiene sensitization drives have been used to prevent new cholera infections. The implementation of these interventions remains a challenge due to constraints associated with the cost, ease of use and technical knowhow. These challenges have been reduced through the use of solar water disinfection (SODIS). The success of SODIS in mitigating the risk associated with the consumption of waterborne pathogens has been associated with solar irradiation. This has prompted a lot of focus on the solar component for enhanced disinfection. However, the role played by the host immune system following the consumption of solar-irradiated water pathogens has not received any significant attention. The mode of inactivation resulting from the exposure of microbiologically contaminated water results in immunologically important microbial states as well as components. In this review, the possible influence that solar water disinfection may have on the immunity against cholera is discussed.


Asunto(s)
Cólera/prevención & control , Desinfección/métodos , Agua Potable/microbiología , Inmunidad Mucosa , Luz Solar , Vibrio cholerae/efectos de la radiación , Cólera/microbiología , Desinfección/normas , Humanos
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