At the end of a nice blog by Erica Verillo on "Slow Sepsis - gut induced inflammation in ME/CFS she suggests five types of supplements that might be able to help with healing the gut lining
Zinc carnosine: A 2007 study by A Mahmood et al, found that zinc carnosine stimulates gut repair processes. (You can read the full study here.)
Fiber: There is considerable debate about whether insoluble fiber (cellulose) is better for restoring the gut lining than soluble fiber. Research supports the idea that insoluble fiber is better for intestinal health, and that large amounts of soluble fiber may actually impair gut health (Shiao and Chang, 1986). In any case, diets that do not contain fiber increase intestinal permeability (G Spaeth, 1990).
Essential fatty acids (EFAs): Essential fatty acids, such as fish oil, flaxseed oil and borage oil, can help repair injury to the lining of the gut and restore gut mucosa. EFAs also limit the harmful effects created by the translocation of endotoxins (gram-negative bacteria found in the large intestine) (Vanderhoof et al. 1991).
Antioxidants: In 2008, M. Maes and J.C. Leunis found that leaky gut in patients with ME/CFS could be corrected with natural anti-inflammatories and antioxidants. Some of the antioxidants that have been reported as helpful for leaky gut are: NAC, Glutathione, and Gamma oryzanol.
Butyrates: Butyrates (also called butyric acid) are short-chain fatty acids produced in the colon by the fermentation of carbohydates through the action of intestinal flora. Butyrates enable your gut to function. Without them, the cells that line your intestines die by autophagy (they eat themselves). Butryrates are found naturally in butter. They can also be taken as a supplement (ButyrEn).