Brown fat is said to be “good”. It is known that it plays an important role in thermogenesis and maintains body joto when exposed to cold conditions. An increase in amount of BAT and/or its activation has been shown to be positively correlated with improvement of cardiometabolic health. Wanyama studies have shown that the brown fat can be increased/activated by exposure to cold conditions, reduced exposure to light and/or upregulation of specific genes. Further research and extensive binadamu trials are needed to establish the importance of increased activation of BAT in improving cardiometabolic afya.
Brown fat is also called brown adipose tissue or BAT in short. It is a special type of body fat that is turned on (activated) when we experience cold. The heat produced by brown fat helps maintain our body joto in cold conditions. The function of BAT is to transfer energy from chakula into heat; physiologically, both the heat produced and the resulting decrease in metabolic efficiency is of great significance for the body. Heat production from brown adipose tissue is activated whenever the organism is in need of extra heat, e.g., among new-borns soon after birth and during fever when body temperature increases. Brown fat cells possess multilocular lipid droplets and large numbers of mitochondria that contain a unique protein called uncoupling protini 1 (UCP1) (1). Ukuaji wa tishu za adipose ya kahawia pamoja na protini-1 (UCP1) inayounganisha, labda inawajibika kwa mafanikio ya mageuzi ya mamalia kama viumbe vya hewa, kwani thermogenesis yake huongeza maisha ya watoto wachanga na inaruhusu maisha hai chini ya hali ya baridi. (2).
Uwepo wa BAT umehusishwa vyema na afya ya cardiometabolic. Watu walio na BAT wamepunguza unene na wana kiwango kidogo cha maambukizi ya aina ya 2 ya kisukari (ongezeko la unyeti wa insulini), dyslipidemia, ugonjwa wa moyo, ugonjwa wa cerebrovascular, kushindwa kwa moyo na shinikizo la damu. Matokeo haya yaliungwa mkono na uboreshaji wa glukosi ya damu (maadili ya chini), na kuongezeka kwa viwango vya lipoproteini za juu-wiani. Zaidi ya hayo, athari za manufaa za BAT zilijulikana zaidi kwa watu wanene, ikionyesha kwamba BAT inaweza pia kuwa na jukumu katika kupunguza madhara ya fetma. (3). Uwepo na kazi ya BAT inaweza kuwa na athari kwa janga la hivi majuzi lililosababishwa na COVID-19. Inazidi kuwa wazi kuwa watu wanene walio na tishu nyeupe zaidi za mafuta (WAT) wanaweza kuwa na uwezekano wa kuwa na na kuambukizwa COVID-19 kali. (4) na inaweza kudhaniwa kuwa uwepo wa BAT unaweza kuwa na athari ya manufaa kuhusiana na kuambukizwa ugonjwa wa COVID-19.
Ushahidi wa utafiti wa hivi majuzi unapendekeza kwamba kutumia hatua za kimatibabu kama vile matumizi ya mirabegron, kipokezi cha adrenergic beta 3, kunaweza kuboresha ugonjwa wa kimetaboliki unaohusiana na unene kwa kuongeza thermogenesis ya tishu za kahawia (BAT). Kwa kweli, matokeo ya sugu matibabu ya mirabegron ilionyesha kuongezeka kwa shughuli za kimetaboliki ya BAT, bila mabadiliko makubwa katika uzito wa mwili au muundo. Kwa kuongeza, viwango vya plasma vya alama za bioalama za lipoprotein zenye manufaa HDL na ApoA1 (apolipoprotein A1) zilipatikana kuwa za juu zaidi. Adiponectin, homoni inayotokana na WAT ambayo ina uwezo wa kupambana na kisukari na kupambana na uchochezi, pia ilionyesha ongezeko la 35% baada ya kukamilika kwa utafiti. Hizi ziliunganishwa na unyeti wa juu wa insulini na usiri wa insulini(5).
Ni nini athari za uwepo au athari za faida za BAT kwa mtu wa kawaida? Je, tunaweza kuwezesha BAT kwa kupunguzwa kwa mwangaza au kwa kudhibiti jeni zinazoonyeshwa katika BAT au kwa kukabiliwa na hali ya baridi? Angalau, utafiti juu ya panya unatoa mwanga juu ya haya (6,7) na inaweza kuweka njia ya kuanzishwa zaidi kwa masomo juu ya wanadamu.
Je, hiyo inamaanisha kuwa mfiduo wa halijoto baridi huwezesha BAT na/au huongeza kiasi cha BAT? Jaribio la nasibu la mfiduo wa baridi kwa wanadamu kwa saa 1 kwa siku kwa wiki 6 lilisababisha kuongezeka kwa kiwango cha BAT. (8).
Utafiti zaidi na majaribio ya kina ya wanadamu yanahitajika ili kuleta athari za faida za BAT kwa wanadamu.
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Marejeo:
- Liangyou R. 2017. Brown na Beige adipose tishu katika afya na ugonjwa. Compr Physiol. 2017 Sep 12; 7(4): 1281–1306. DOI: https://doi.org/10.1002/cphy.c17001
- Cannon B., na Jan Nedergaard J., 2004. Tissue ya adipose ya kahawia: kazi na umuhimu wa kisaikolojia. Uhakiki wa Kifiziolojia. 2004 Jan;84(1):277-359. DOI: https://doi.org/10.1152/physrev.00015.2003
- Becher, T., Palanisamy, S., Kramer, DJ et al. 2021 Tishu ya kahawia ya mafuta inahusishwa na afya ya moyo na mishipa. Iliyochapishwa: 04 Januari 2021. Dawa ya Asili (2021). DOI: https://doi.org/10.1038/s41591-020-1126-7
- Dugail I, Amri EZ na Vitale N. Maambukizi ya juu ya ugonjwa wa kunona kupita kiasi katika COVID-19: Viungo na mitazamo inayowezekana kuelekea utabaka wa wagonjwa, Biochimie, Juzuu 179, 2020, Kurasa 257-265, ISSN 0300-9084. DOI: https://doi.org/10.1016/j.biochi.2020.07.001.
- O'Mara A., Johnson J., Linderman J., 2020. Matibabu ya kudumu ya mirabegroni huongeza mafuta ya hudhurungi ya binadamu, cholesterol ya HDL na usikivu wa insulini. Ilichapishwa Januari 21, 2020. Journal of Clinical Investigation Juzu 130, Toleo la 5 mnamo Mei 1, 2020, 2209–2219. DOI: https://doi.org/10.1172/JCI131126
- Shultz D. Je, kuzima taa kunaweza kukusaidia kuchoma mafuta? Biolojia. 2015, DOI: https://doi.org/10.1126/science.aac4580
- Houtkooper R., 2018. Fat up to BAT. Bilim Translational Medicine 04 Jul 2018: Vol. 10, Issue 448, eaau1972. DOI: https://doi.org/10.1126/scitranslmed.aau1972
- Jaribio la nasibu la mfiduo baridi juu ya matumizi ya nishati na kiasi cha tishu za adipose ya hudhurungi kwa wanadamu. DOI: https://doi.org/10.1016/j.metabol.2016.03.012
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