Here is a quotation from the following 2008 paper:

"Vitamin C supplementation lowers serum low-density lipoprotein cholesterol and triglycerides: a meta-analysis of 13 randomized controlled trials"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682928/

"In regard to mechanism of action, it has been shown that vitamin C is able to intercept reactive oxygen species in the aqueous phase of plasma, thereby significantly reducing plasma lipid peroxide levels and thus inhibiting oxidative modification of LDLs.47-49 This protection preserves the ability of LDL to be recognized by LDL receptors in the liver and therefore expedite its removal from the blood by LDL cholesterol catabolic pathways.50 Vitamin C may also have a protective effect on these LDL receptors that were shown to decrease in number by approximately 25% in guinea pigs fed suboptimal vitamin C intakes.51 This same guinea pig study also found that suboptimal vitamin C intake caused an increase in the activity of 2 cholesterol-regulating enzymes, acyl–coenzyme A:cholesterol acyltransferase and cholesterol ester transfer protein, by 20% and 30%, respectively. Increased activity of acyl–coenzyme A:cholesterol acyltransferase may result in elevated serum LDL cholesterol concentrations,52 where an increase in cholesterol ester transfer protein activity may cause a reduction in HDL cholesterol.53"

I have no idea whether this association has held up. Perhaps not, as suggested by this 2016 web page, from the University of Maryland Medical Center:

http://umm.edu/health/medical/altmed/supplement/vitamin-c-ascorbic-acid

"Results of scientific studies on whether vitamin C is helpful for preventing heart attack or stroke are mixed. Vitamin C doesn't lower cholesterol levels or reduce the overall risk of heart attack, but evidence suggests it may help protect arteries against damage.

Some studies -- though not all -- suggest that vitamin C can slow down the progression of atherosclerosis (hardening of the arteries). It helps prevent damage to LDL ("bad") cholesterol, which then builds up as plaque in the arteries and can cause heart attack or stroke. Other studies suggest that vitamin C may help keep arteries flexible.

In addition, people who have low levels of vitamin C may be more likely to have a heart attack, stroke, or peripheral artery disease, all potential results of having atherosclerosis. Peripheral artery disease is the term used to describe atherosclerosis of the blood vessels to the legs. This can lead to pain when walking, known as intermittent claudication. But there is no evidence that taking vitamin C supplements will help."

The problem with investigating a subject like this is that there are a lot of biased sources, especially those touting "natural" dietary supplements over prescription pharmaceuticals.

Thank you so much for your rapid response, Dr Shapiro.

Still looking forward more precise explainations about the link between Vitamin C and level of LDH (Lactate Dehydrogenase Isozymes).

Dear

Two types of genetic mutations cause low LDH levels. People with the first type will experience fatigue and muscle pain, while those with the second type may have no symptoms at all. You may also have low LDH levels if you’ve consumed a large amount of ascorbic acid (vitamin C).

Thank

Marius

Oops. I misread the question.

I saw some references to vitamin C consumption being associated with low LDH levels, but not on the mechanism. One possibility is that ascorbic acid interferes in the LDH assay, and therefore the apparent decrease in LDH is an artifact. However, I also found this review on the linkage between ascorbic acid and lactate metabolism in the brain:

https://www.ncbi.nlm.nih.gov/pubmed/19457103