Lactate, or lactic acid anion, is a relatively large and long-standing topic in our laboratory. We have all probably heard the term in relation to the human body at some point, most often in connection with physical exhaustion. Indeed, for a long time, lactate was viewed only as a waste product of anaerobic glycolysis when there is an inadequate supply of oxygen to the tissues, which is responsible for muscle pain and fatigue. However, nothing is black and white, and recent research has partially contradicted these findings while showing that it can also be beneficial to the body, as it is also an important signalling molecule involved in several metabolic processes or a non-negligible energy source for our nerve cells.
So how's the whole lactate thing going? Generally speaking, lactate can have both a positive and negative role in the context of the human body. In particular, lactate produced by tumour and ischemic tissue has adverse effects. On the other hand, positive effects have been observed for lactate produced during physical exertion or consumed as a functional component (postbiotic) of fermented foods, including, for example, adaptation of the body to stress conditions through mitochondrial hormesis, faster tissue regeneration and, in turn, delayed ageing, or control of adipose tissue homeostasis and reduced risk of obesity and insulin resistance.
In our laboratory, we are working on several projects focusing mainly on lactate and its health benefits. For example, we are looking at the effects of lactate at the cellular level in human fibroblast tissue lines. We interact with lactate over a long period of time to simulate the situation that occurs in the body during and after intense exercise and try to detect any physiological changes in these cells. In particular, we focus on differences in growth rate and the transition to senescence. We also look at effects on cellular antioxidant mechanisms and mitochondrial activity or potential protection against carcinogenesis. However, we are not limited to single cells and tissue lines, our laboratory is also involved in investigating the effects of lactate in mouse models that have been supplemented with lactate in their diet. We are currently working on analysing their gut microbiome and liver proteome to discover either positive or negative changes that could be related to the presence of lactate in the diet. Ideally, we could thus get an answer to the question of what is the essence of the benefits of eating fermented foods, or theoretically contribute to the development of a lactate-based drug that would target the alleviation of civilisation diseases, which is and unfortunately will undoubtedly be even more of a problem in the human population in the future.
