Solamargine, a bioactive steroidal alkaloid isolated from Solanum aculeastrum induces non-selective cytotoxicity and P-glycoprotein inhibition

Table 3 Synergistic potential of solamargine and the aqueous alkaloid-enriched fraction as described by their FIX values in a panel of cancerous and non-cancerous cell lines

Cell type	Cancerous				Non-cancerous
Cell line	SH-SY5Y		SK-Br3		C2C12		EA.hy926
Compound/Fraction	Solamargine	Aqueous alkaloid-enriched fraction	Solamargine	Aqueous alkaloid-enriched fraction	Solamargine	Aqueous alkaloid-enriched fraction	Solamargine	Aqueous alkaloid-enriched fraction
IC₅₀ of (A) [IC₅₀ sample + doxorubicin (μM or μg/mL)]	3.4	7.39	4.3	11.18	30.77	15.7	5.5	2.62
IC₅₀ of (B) [IC₅₀ doxorubicin + sample (nM)]	16.27	24.22	40.83	47.48	149.9	140.7	213.4	220
IC₅₀ (A) [Solamargine (μM) or aqueous alone (μg/mL)]	15.62	26.5	18.59	19.7	20.25	13.7	8.3	7.3
IC₅₀ (B) [doxorubicin alone (nM)]	56.6	56.6	94.1	94.1	148.5	148.5	381.6	381.6
FIC (A)	0.22	0.28	0.23	0.57	1.52	1.15	0.66	0.36
FIC (B)	0.29	0.43	0.43	0.5	1.01	0.95	0.56	0.58
FIX value	0.51	0.71	0.66	1.07	2.53	2.1	1.22	0.94
Result	Additive effect	Additive effect	Additive effect	Indifferent effect	Antagonistic effect	Antagonistic effect	Indifferent effect	Additive effect