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Cai J, Quan Y, Zhu S, Jiayan Lin, Zhang Q, Liu J, Liang Z, Liao Y, Jiang W, He Y, Su T, Lu F. The browning and mobilization of subcutaneous white adipose tissue supports efficient skin repair. Cell Metab 2024; 36:1287-1301.e7. [PMID: 38838641 DOI: 10.1016/j.cmet.2024.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 03/05/2024] [Accepted: 05/08/2024] [Indexed: 06/07/2024]
Abstract
Adipocytes in dermis are considered to be important participants in skin repair and regeneration, but the role of subcutaneous white adipose tissue (sWAT) in skin repair is poorly understood. Here, we revealed the dynamic changes of sWAT during wound healing process. Lineage-tracing mouse studies revealed that sWAT would enter into the large wound bed and participate in the formation of granulation tissue. Moreover, sWAT undergoes beiging after skin injury. Inhibition of sWAT beiging by genetically silencing PRDM16, a key regulator to beiging, hindered wound healing process. The transcriptomics results suggested that beige adipocytes in sWAT abundantly express neuregulin 4 (NRG4), which regulated macrophage polarization and the function of myofibroblasts. In diabetic wounds, the beiging of sWAT was significantly suppressed. Thus, adipocytes from sWAT regulate multiple aspects of repair and may be therapeutic for inflammatory diseases and defective wound healing associated with aging and diabetes.
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Affiliation(s)
- Junrong Cai
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Yuping Quan
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Shaowei Zhu
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Jiayan Lin
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Qian Zhang
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Juzi Liu
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Zhuokai Liang
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Yunjun Liao
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Wenqing Jiang
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Yufei He
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China
| | - Ting Su
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China.
| | - Feng Lu
- Department of Plastic and Cosmetic Surgery, Nanfang Hospital, Southern Medical University, 1838 Guangzhou North Road, Guangzhou, Guangdong 510515, P.R. China.
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Peng Y, Zhao L, Li M, Liu Y, Shi Y, Zhang J. Plasticity of Adipose Tissues: Interconversion among White, Brown, and Beige Fat and Its Role in Energy Homeostasis. Biomolecules 2024; 14:483. [PMID: 38672499 PMCID: PMC11048349 DOI: 10.3390/biom14040483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 04/08/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
Obesity, characterized by the excessive accumulation of adipose tissue, has emerged as a major public health concern worldwide. To develop effective strategies for treating obesity, it is essential to comprehend the biological properties of different adipose tissue types and their respective roles in maintaining energy balance. Adipose tissue serves as a crucial organ for energy storage and metabolism in the human body, with functions extending beyond simple fat storage to encompass the regulation of energy homeostasis and the secretion of endocrine factors. This review provides an overview of the key characteristics, functional differences, and interconversion processes among white adipose tissue (WAT), brown adipose tissue (BAT), and beige adipose tissue. Moreover, it delves into the molecular mechanisms and recent research advancements concerning the browning of WAT, activation of BAT, and whitening of BAT. Although targeting adipose tissue metabolism holds promise as a potential approach for obesity treatment, further investigations are necessary to unravel the intricate biological features of various adipose tissue types and elucidate the molecular pathways governing their interconversion. Such research endeavors will pave the way for the development of more efficient and targeted therapeutic interventions in the fight against obesity.
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Affiliation(s)
| | | | | | | | | | - Jian Zhang
- School of Bioengineering, Zunyi Medical University, Zhuhai 519000, China; (Y.P.); (L.Z.); (M.L.); (Y.L.); (Y.S.)
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Flori L, Piragine E, Calderone V, Testai L. Role of hydrogen sulfide in the regulation of lipid metabolism: Implications on cardiovascular health. Life Sci 2024; 341:122491. [PMID: 38336275 DOI: 10.1016/j.lfs.2024.122491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/29/2024] [Accepted: 02/05/2024] [Indexed: 02/12/2024]
Abstract
The World Health Organization (WHO) defines obesity as an urgency for health and a social emergency. Today around 39 % of people is overweight, of these over 13 % is obese. It is well-consolidated that the adipose cells are deputy to lipid storage under caloric excess; however, despite the classical idea that adipose tissue has exclusively a passive function, now it is known to be deeply involved in the regulation of systemic metabolism in physiological as well as under obesogenic conditions, with consequences on cardiovascular health. Beside two traditional types of adipose cells (white and brown), recently the beige one has been highlighted as the consequence of the healthy remodeling of white adipocytes, confirming their metabolic adaptability. In this direction, pharmacological, nutraceutical and nutrient-based approaches are addressed to positively influence inflammation and metabolism, thus contributing to reduce the obese-associated cardiovascular risk. In this scenario, hydrogen sulfide emerges as a new mediator that may regulate crucial targets involved in the regulation of metabolism. The current evidence demonstrates that hydrogen sulfide may induce peroxisome proliferator activated receptor γ (PPARγ), a crucial mediator of adipogenesis, inhibit the phosphorylation of perlipin-1 (plin-1), a protein implicated in the lipolysis, and finally promote browning process, through the release of irisin from skeletal muscle. The results summarized in this review suggest an important role of hydrogen sulfide in the regulation of metabolism and in the prevention/treatment of obese-associated cardiovascular diseases and propose new insight on the putative mechanisms underlying the release of hydrogen sulfide or its biosynthesis, delineating a further exciting field of application.
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Affiliation(s)
- Lorenzo Flori
- Department of Pharmacy, University of Pisa, via Bonanno, 6-56120 Pisa, Italy.
| | - Eugenia Piragine
- Department of Pharmacy, University of Pisa, via Bonanno, 6-56120 Pisa, Italy.
| | - Vincenzo Calderone
- Department of Pharmacy, University of Pisa, via Bonanno, 6-56120 Pisa, Italy.
| | - Lara Testai
- Department of Pharmacy, University of Pisa, via Bonanno, 6-56120 Pisa, Italy.
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Egashira K, Kajiya H, Tsutsumi T, Taniguchi Y, Kakura K, Ohno J, Kido H. AMPK activation enhances osteoblast differentiation on a titanium disc via autophagy. Int J Implant Dent 2024; 10:2. [PMID: 38286943 PMCID: PMC10825085 DOI: 10.1186/s40729-024-00525-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/18/2024] [Indexed: 01/31/2024] Open
Abstract
PURPOSE The acquisition of osseointegration during implant therapy is slower and poorer in patients with diabetes compared with healthy persons. The serum concentration of adiponectin in patients with type II diabetes is lower than that of healthy persons via the suppression of AMP-activated protein kinase (AMPK). Therefore, we hypothesized that the AMPK activation enhances bone formation around implants, resulting in the improved acquisition of osseointegration. The purpose of this study was to evaluate the impact of AMPK activation on osteoblast differentiation and its mechanism of downstream signaling on titanium disc (Ti). METHODS Confluent mouse pre-osteoblasts (MC3T3-E1) cells (1 × 105 cells/well) were cultured with BMP-2 for osteoblast differentiation, in the presence or absence AICAR, an AMPK activator. We examined the effects of AMPK activation on osteoblast differentiation and the underlying mechanism on a Ti using a CCK8 assay, a luciferase assay, quantitative RT-PCR, and western blotting. RESULTS Although the proliferation rate of osteoblasts was not different between a Ti and a tissue culture polystyrene dish, the addition of AICAR, AMPK activator slightly enhanced osteoblast proliferation on the Ti. AICAR enhanced the BMP-2-dependent transcriptional activity on the Ti, leading to upregulation in the expression of osteogenesis-associated molecules. AICAR simultaneously upregulated the expression of autophagy-associated molecules on the Ti, especially LC3-II. AdipoRon, an adiponectin receptor type1/type2 activator activated AMPK, and upregulated osteogenesis-associated molecules on Ti. CONCLUSIONS AMPK activation enhances osteoblast differentiation on a Ti via autophagy, suggesting that it promotes the acquisition of osseointegration during implant therapy.
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Affiliation(s)
- Kei Egashira
- Section of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, Fukuoka, Japan
- Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
| | - Hiroshi Kajiya
- Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan.
- Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, 814-0193, Japan.
| | - Takashi Tsutsumi
- Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
- Department of General Dentistry, Fukuoka Dental College, Fukuoka, Japan
| | - Yusuke Taniguchi
- Section of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, Fukuoka, Japan
| | - Kae Kakura
- Section of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, Fukuoka, Japan
| | - Jun Ohno
- Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
| | - Hirofumi Kido
- Section of Oral Implantology, Department of Oral Rehabilitation, Fukuoka Dental College, Fukuoka, Japan
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Ziqubu K, Dludla PV, Mabhida SE, Jack BU, Keipert S, Jastroch M, Mazibuko-Mbeje SE. Brown adipose tissue-derived metabolites and their role in regulating metabolism. Metabolism 2024; 150:155709. [PMID: 37866810 DOI: 10.1016/j.metabol.2023.155709] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 09/28/2023] [Accepted: 10/14/2023] [Indexed: 10/24/2023]
Abstract
The discovery and rejuvenation of metabolically active brown adipose tissue (BAT) in adult humans have offered a new approach to treat obesity and metabolic diseases. Beyond its accomplished role in adaptive thermogenesis, BAT secretes signaling molecules known as "batokines", which are instrumental in regulating whole-body metabolism via autocrine, paracrine, and endocrine action. In addition to the intrinsic BAT metabolite-oxidizing activity, the endocrine functions of these molecules may help to explain the association between BAT activity and a healthy systemic metabolic profile. Herein, we review the evidence that underscores the significance of BAT-derived metabolites, especially highlighting their role in controlling physiological and metabolic processes involving thermogenesis, substrate metabolism, and other essential biological processes. The conversation extends to their capacity to enhance energy expenditure and mitigate features of obesity and its related metabolic complications. Thus, metabolites derived from BAT may provide new avenues for the discovery of metabolic health-promoting drugs with far-reaching impacts. This review aims to dissect the complexities of the secretory role of BAT in modulating local and systemic metabolism in metabolic health and disease.
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Affiliation(s)
- Khanyisani Ziqubu
- Department of Biochemistry, North-West University, Mmabatho 2745, South Africa
| | - Phiwayinkosi V Dludla
- Cochrane South Africa, South African Medical Research Council, Tygerberg 7505, South Africa; Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa
| | - Sihle E Mabhida
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Babalwa U Jack
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Susanne Keipert
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Martin Jastroch
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
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Pestel J, Blangero F, Watson J, Pirola L, Eljaafari A. Adipokines in obesity and metabolic-related-diseases. Biochimie 2023; 212:48-59. [PMID: 37068579 DOI: 10.1016/j.biochi.2023.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/03/2023] [Accepted: 04/13/2023] [Indexed: 04/19/2023]
Abstract
The discovery of leptin in the 1990s led to a reconsideration of adipose tissue (AT) as not only a fatty acid storage organ, but also a proper endocrine tissue. AT is indeed capable of secreting bioactive molecules called adipokines for white AT or batokines for brown/beige AT, which allow communication with numerous organs, especially brain, heart, liver, pancreas, and/or the vascular system. Adipokines exert pro or anti-inflammatory activities. An equilibrated balance between these two sets ensures homeostasis of numerous tissues and organs. During the development of obesity, AT remodelling leads to an alteration of its endocrine activity, with increased secretion of pro-inflammatory adipokines relative to the anti-inflammatory ones, as shown in the graphical abstract. Pro-inflammatory adipokines take part in the initiation of local and systemic inflammation during obesity and contribute to comorbidities associated to obesity, as detailed in the present review.
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Affiliation(s)
- Julien Pestel
- INSERM U1060-CarMeN /Université Claude Bernard Lyon 1/INRAE/ Université Claude Bernard Lyon 1: Laboratoire CarMeN, 165 chemin du Grand Revoyet, CHLS, 69310 Pierre Bénite, France
| | - Ferdinand Blangero
- INSERM U1060-CarMeN /Université Claude Bernard Lyon 1/INRAE/ Université Claude Bernard Lyon 1: Laboratoire CarMeN, 165 chemin du Grand Revoyet, CHLS, 69310 Pierre Bénite, France
| | - Julia Watson
- INSERM U1060-CarMeN /Université Claude Bernard Lyon 1/INRAE/ Université Claude Bernard Lyon 1: Laboratoire CarMeN, 165 chemin du Grand Revoyet, CHLS, 69310 Pierre Bénite, France
| | - Luciano Pirola
- INSERM U1060-CarMeN /Université Claude Bernard Lyon 1/INRAE/ Université Claude Bernard Lyon 1: Laboratoire CarMeN, 165 chemin du Grand Revoyet, CHLS, 69310 Pierre Bénite, France
| | - Assia Eljaafari
- INSERM U1060-CarMeN /Université Claude Bernard Lyon 1/INRAE/ Université Claude Bernard Lyon 1: Laboratoire CarMeN, 165 chemin du Grand Revoyet, CHLS, 69310 Pierre Bénite, France; Hospices Civils de Lyon: 2 quai des Célestins, 69001 Lyon, France.
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Sarlon J, Partonen T, Lang UE. Potential links between brown adipose tissue, circadian dysregulation, and suicide risk. Front Neurosci 2023; 17:1196029. [PMID: 37360180 PMCID: PMC10288144 DOI: 10.3389/fnins.2023.1196029] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/12/2023] [Indexed: 06/28/2023] Open
Abstract
Circadian desynchronizations are associated with psychiatric disorders as well as with higher suicidal risk. Brown adipose tissue (BAT) is important in the regulation of body temperature and contributes to the homeostasis of the metabolic, cardiovascular, skeletal muscle or central nervous system. BAT is under neuronal, hormonal and immune control and secrets batokines: i.e., autocrine, paracrine and endocrine active substances. Moreover, BAT is involved in circadian system. Light, ambient temperature as well as exogen substances interact with BAT. Thus, a dysregulation of BAT can indirectly worsen psychiatric conditions and the risk of suicide, as one of previously suggested explanations for the seasonality of suicide rate. Furthermore, overactivation of BAT is associated with lower body weight and lower level of blood lipids. Reduced body mass index (BMI) or decrease in BMI respectively, as well as lower triglyceride concentrations were found to correlate with higher risk of suicide, however the findings are inconclusive. Hyperactivation or dysregulation of BAT in relation to the circadian system as a possible common factor is discussed. Interestingly, substances with proven efficacy in reducing suicidal risk, like clozapine or lithium, interact with BAT. The effects of clozapine on fat tissue are stronger and might differ qualitatively from other antipsychotics; however, the significance remains unclear. We suggest that BAT is involved in the brain/environment homeostasis and deserves attention from a psychiatric point of view. Better understanding of circadian disruptions and its mechanisms can contribute to personalized diagnostic and therapy as well as better assessment of suicide risk.
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Affiliation(s)
- Jan Sarlon
- University Psychiatric Clinics (UPK), University of Basel, Basel, Switzerland
| | - Timo Partonen
- Department of Public Health and Welfare, Finnish Institute for Health and Welfare (THL), Helsinki, Finland
| | - Undine E. Lang
- University Psychiatric Clinics (UPK), University of Basel, Basel, Switzerland
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Zhu T, Chen X, Jiang S. Progress and obstacles in transplantation of brown adipose tissue or engineered cells with thermogenic potential for metabolic benefits. Front Endocrinol (Lausanne) 2023; 14:1191278. [PMID: 37265692 PMCID: PMC10230949 DOI: 10.3389/fendo.2023.1191278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/27/2023] [Indexed: 06/03/2023] Open
Abstract
Transplantation of brown adipose tissue (BAT), engineered thermogenic progenitor cells, and adipocytes have received much attention for the improvement of obesity and metabolic disorders. However, even though the thermogenic and metabolic potential exists early after transplantation, the whitening of the brown fat graft occurs with metabolic function significantly impaired. In this review, specific experiment designs, graft outcomes, and metabolic benefits for the transplantation of BAT or engineered cells will be discussed. The current advancements will offer guidance to further investigation, and the obstacles appearing in previous studies will require innovation of BAT transplantation methods.
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Ziqubu K, Dludla PV, Mthembu SXH, Nkambule BB, Mabhida SE, Jack BU, Nyambuya TM, Mazibuko-Mbeje SE. An insight into brown/beige adipose tissue whitening, a metabolic complication of obesity with the multifactorial origin. Front Endocrinol (Lausanne) 2023; 14:1114767. [PMID: 36875450 PMCID: PMC9978510 DOI: 10.3389/fendo.2023.1114767] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023] Open
Abstract
Brown adipose tissue (BAT), a thermoregulatory organ known to promote energy expenditure, has been extensively studied as a potential avenue to combat obesity. Although BAT is the opposite of white adipose tissue (WAT) which is responsible for energy storage, BAT shares thermogenic capacity with beige adipose tissue that emerges from WAT depots. This is unsurprising as both BAT and beige adipose tissue display a huge difference from WAT in terms of their secretory profile and physiological role. In obesity, the content of BAT and beige adipose tissue declines as these tissues acquire the WAT characteristics via the process called "whitening". This process has been rarely explored for its implication in obesity, whether it contributes to or exacerbates obesity. Emerging research has demonstrated that BAT/beige adipose tissue whitening is a sophisticated metabolic complication of obesity that is linked to multiple factors. The current review provides clarification on the influence of various factors such as diet, age, genetics, thermoneutrality, and chemical exposure on BAT/beige adipose tissue whitening. Moreover, the defects and mechanisms that underpin the whitening are described. Notably, the BAT/beige adipose tissue whitening can be marked by the accumulation of large unilocular lipid droplets, mitochondrial degeneration, and collapsed thermogenic capacity, by the virtue of mitochondrial dysfunction, devascularization, autophagy, and inflammation.
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Affiliation(s)
- Khanyisani Ziqubu
- Department of Biochemistry, North-West University, Mmabatho, South Africa
| | - Phiwayinkosi V. Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa, South Africa
| | - Sinenhlanhla X. H. Mthembu
- Department of Biochemistry, North-West University, Mmabatho, South Africa
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Bongani B. Nkambule
- School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Sihle E. Mabhida
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Babalwa U. Jack
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Tawanda M. Nyambuya
- Department of Health Sciences, Faculty of Health and Applied Sciences, Namibia University of Science and Technology, Windhoek, Namibia
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