Table 1. Effect of HB (1) and its analogues (2–9) on protein accumulation in the L6 rat skeletal muscle cells.

Compounds were tested at 10 μM and results are expressed as the mean ± SEM of determinations performed in triplicate (* P<0.05, ** P<0.01, *** P<0.001 when compared with control by one-way ANOVA and Dunnett’s post-test).

ID	Common name	Chemical name	Formula	MW	Protein syn- thesis, % increase over control	Protein deg- radation, % decrease over control
1	(22S,23S)-homobrassinolide	(22S,23S,24S)-2α,3α,22,23-tetrahydroxy- B- homo-7-oxa- 5α-cholestan-6-one	C29H50O6	494.70	37 ± 6***	−24 ± 6*
2	(22S,23S)-homocastasterone	(22S,23S,24S)-2α,3α,22,23-tetrahydroxy-24- ethyl- 5α-cholestan-6-one	C29H50O5	478.70	41 ± 3***	−23 ± 4*
3	(22S,23S)-3α-fluoro- homobrasinolide	(22S,23S,24R)-3α-fluoro-22,23-dihydroxy- 24-ethyl-B-homo-7-oxa- 5α-cholestan-6-one	C29H49FO4	480.70	25 ± 5**	−21 ± 1*
4	(22S,23S)-3α-fluoro- homocastasterone	(22S,23S,24S)-3α-fluoro-22,23-dihydroxy- 24-ethyl- 5α-cholestan-6-one	C29H49FO3	464.70	23 ± 3**	−16 ± 4
5	(22S,23S)-7v-aza- homobrassinolide	(22S,23S,24S)-2α,3α,22,23-tetrahydroxy-24- ethyl- B-homo-7-aza- 5α-cholestan-6-one	C29H51NO5	493.72	21 ± 2**	−1 ± 3
6	(22S,23S)-6-aza- homobrassinolide	(22S,23S,24S)-2α,3α,22,23-tetrahydroxy-24- ethyl- B-homo-6-aza- 5α-cholestan-7-one	C29H51NO5	493.72	3 ± 12	−14 ± 4
7	(22R,23R)-homobrassinolide	(22R,23R,24S)-2α,3α,22,23-tetrahydroxy- B- homo-7-oxa- 5α-cholestan-6-one	C29H50O6	494.70	13 ± 2	−15 ± 4
8	(22S,23S)-epibrassinolide	(22S,23S,24R)-2α,3α,22,23-tetrahydroxy-24- methyl-B-homo-7-oxa- 5α-cholestan-6-one	C28H48O6	480.68	4 ± 2	−6 ± 8
9	(22R,23R)-epibrassinolide	(22R,23R,24R)-2α,3α,22,23-tetrahydroxy-24- methyl-B-homo-7-oxa-5α-cholestan-6-one	C28H48O6	480.68	12 ± 4	−7 ± 8
Ref	IGF-1, 6.5 nM	Positive control			43 ± 5***	--
Ref	Insulin, 10 nM	Positive control			--	−20 ± 2*