Effects of Aloe vera on gap junctional intercellular communication and proliferation of human diabetic and nondiabetic skin fibroblasts.
OBJECTIVE
To evaluate the effects of Aloe vera on gap junctional intercellular communication (GJIC) and proliferation of human skin fibroblasts in the presence or absence of basic fibroblast growth factor (FGF-2).


METHODS
In vitro study using human type II diabetic and nondiabetic skin fibroblast cell lines.


METHODS
Diabetic (n = 4) and nondiabetic (n = 4) human skin fibroblast cell lines were purchased from Coriell Institute for Medical Research (Camden, NJ). The cells were cultured with or without Aloe vera extract in increasing concentrations (0%, 0.625%, 1.25%, 2.5%, 5%, 10%, and 20%; v/v) in culture medium and with or without FGF-2 (30 ng/mL).


METHODS
GJIC was evaluated after 48-hour incubation with treatments by laser cytometry. Cells were counted after 72-hour incubation with treatments by using a Coulter counter.


RESULTS
The rate of GJIC was greater (p < 0.01) for diabetic than for nondiabetic fibroblasts (3.5 +/- 0.1 versus 3.0 +/- 0.1% per minute during the first 4 minutes after photobleaching). GJIC was increased ( p < 0.05) for diabetic fibroblasts in the presence of 2.5% and 5% of Aloe vera extract (4.2 +/- 0.1 and 4.0 +/- 0.2 versus 3.5 +/- 0.1% per minute for control, respectively). FGF-2 stimulated (p < 0.01) GJIC for diabetic (4.0 +/- 0.1 versus 3.5 +/- 0.1% per minute for control) and nondiabetic (3.5 +/- 0.1 versus 3.0 +/- 0.1% per minute for control) fibroblasts. Aloe vera extract did not affect GJIC of nondiabetic fibroblast cultured without FGF-2. However, Aloe vera extract decreased (p < 0.05) FGF-2 stimulatory effects on GJIC of diabetic and nondiabetic fibroblasts. Proliferation of diabetic fibroblasts was increased (p < 0.05) by 1.25% and 2.5% Aloe vera extract in medium. Proliferation of nondiabetic fibroblasts was not affected by Aloe vera extract. FGF-2 increased (p < 0.05) proliferation of nondiabetic fibroblasts and FGF-2 did not affect proliferation of diabetic fibroblasts. Aloe vera extract decreased (p < 0.05) FGF-2 stimulatory effects on proliferation of nondiabetic fibroblasts.


CONCLUSIONS
These data demonstrate that Aloe vera has the ability to stimulate GJIC and proliferation of human skin fibroblasts in diabetes mellitus. Furthermore, these results indicate that Aloe vera contains a compound(s) that neutralizes, binds with FGF-2 receptor, or otherwise alters signaling pathways for FGF-2. By affecting both GJIC and proliferation of diabetic fibroblasts, Aloe vera may improve wound healing in diabetes mellitus.
Abdullah
Kay M
KM
Department of Surgery, School of Medicine, University of North Dakota, Grand Forks, ND, USA.
Abdullah
Ahmed
A
Johnson
Mary Lynn
ML
Bilski
Jerzy J
JJ
Petry
Kimberly
K
Redmer
Dale A
DA
Reynolds
Lawrence P
LP
Grazul-Bilska
Anna T
AT
D000504:Aloe; D002450:Cell Communication / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects*; D017629:Gap Junctions / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects* / Q000293:injuries; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects*
D010936:Plant Extracts; D016222:Fibroblast Growth Factor 2